1 10 8 https://apconf-much.org/proceedings/files/original/8489759771419ea3bf73c8974311c153.mp4 dab650ceb26c651f66a17d12afee19d1 Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Session 7: Preservation and Conservation of Wet Archaeological Materials and Site Management Subject The topic of the resource Interview with Session 7 chairs Vicki Richards and Jon Carpenter and links to the papers presented in the session. Description An account of the resource This session will focus on in-situ preservation and conservation management issues, conservation analyses and treatments, and applied conservation research of archaeological materials from freshwater, marine and wet terrestrial sites. The main purposes of this session are to encourage the exchange of ideas and practices as well as the development of conservation networks throughout the region. Presentations, posters and workshops are invited that address any of the following areas: • In situ preservation of marine archaeological materials, including reburial practices • Conservation management of shipwreck sites, including on-site monitoring • Conservation treatment case studies • Research into the analysis and treatment of wet archaeological materials • Review of the status of wet archaeological conservation programs in the Asia Pacific region • Development of collaborative conservation research and treatment programs Suggestions for additional topics are welcomed by the session organizers. Creator An entity primarily responsible for making the resource Vicki Richards and Jon Carpenter Moving Image A series of visual representations that, when shown in succession, impart an impression of motion. Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Video interview with Session 7 chair Vicki Richards and Jon Carpenter. Description An account of the resource This session will focus on in-situ preservation and conservation management issues, conservation analyses and treatments, and applied conservation research of archaeological materials from freshwater, marine and wet terrestrial sites. The main purposes of this session are to encourage the exchange of ideas and practices as well as the development of conservation networks throughout the region. Presentations, posters and workshops are invited that address any of the following areas: • In situ preservation of marine archaeological materials, including reburial practices • Conservation management of shipwreck sites, including on-site monitoring • Conservation treatment case studies • Research into the analysis and treatment of wet archaeological materials • Review of the status of wet archaeological conservation programs in the Asia Pacific region • Development of collaborative conservation research and treatment programs Suggestions for additional topics are welcomed by the session organizers. Creator An entity primarily responsible for making the resource Ian Godfrey, Vicki Richards, and Debra Shefi Date A point or period of time associated with an event in the lifecycle of the resource 6/11/2014 Asia-Pac Session 7 2014 https://apconf-much.org/proceedings/files/original/a04596c95094d335a8db86e0270d06c7.pdf 882271ff5bfeedde5a84e95df79fbd95 PDF Text Text Tracking environmental and historical footprints on Clarence: Comparative XRD analysis of clay-rich sediment samples from a 19th century wreck site in Port Phillip Bay, Victoria, Australia Adele Zubrzycka and Anthony J. Barham Archaeology and Natural History School of Culture, History and Language ANU College of Asia and the Pacific The Australian National University ACT 0200 Australia E-mail: a.zubrzycka@gmail.com Ulrike Troitzsch Earth Materials Group Research School of Earth Sciences ANU College of Physical and Mathematical Sciences The Australian National University ACT 0200 Australia Abstract Little is known about shipbuilding in Australia in the early to mid 19th century. Under the Australian Research Council (ARC) funded Australian Historic Shipwreck Preservation Project (AHSPP) (www.ahspp.org.au), underwater excavations were carried out in AprilMay 2012 on the historic trading schooner Clarence, wrecked in shallow waters at Port Phillip Bay, Victoria in September 1850. During excavations, cores collected by lead investigator Peter Veth and principle investigator Vicki Richards were found to contain clay-rich sediment, thought to be ballast. This discovery stimulated investigations of the micro-sedimentary environments and taphonomy associated with the vessel, especially fine-grain sediment supply to the wreck and current and tidal influences on the stability of sediments lodged in and around the site. In order to address these questions, sediment samples were collected from the wreck, seabed and adjacent shorelines. Clay fractions were analysed at the Australian National University (ANU) using X-Ray Diffraction (XRD). Key objectives were to compare mineral signatures in the 'ballast' from clay-rich sources on the seabed and coastal foreshores possibly incorporated as the vessel foundered. Results successfully differentiate a) individual samples by seabed location and b) “ballast” samples in the wreck structure from sampled points around the wreck. The findings suggest that fine sediment within the Clarence shipwreck is likely to be clay ballast, emplaced at some point during the schooner's working life. The results also inform questions regarding the longer-term conservation of Clarence and similar wrecks located in Australian and Southeast Asian shallow-water settings. 1 �Key words: Clarence, Shipwreck, X-ray Diffraction, Sediment, Ballast, Schooner, Conservation. Introduction Clarence, one of Australia's best preserved carvel-built, two-masted wooden trading schooners (Gesner, 1985), was constructed on the Williams River in New South Wales by Sydney merchants Gordon Sandernais and Thomas Ayers in 1841 (Coroneos, 1991). At the time, the Williams River shipbuilding industry was in its early stages of growth, producing unique examples of early shipbuilding techniques in Australia (Taylor, 1977). Small wooden coastal trading vessels were integral to the survival and development of Australia in the early to mid-19th century before the adoption of steam transport (Taylor, 1977). For the next nine years, Clarence worked as a trade vessel, transporting goods and passengers to and from Victoria, New South Wales and Tasmania. On the 2nd of September 1850, the vessel foundered on a sand bank in Port Phillip Bay while transporting sheep and other goods from Melbourne to Hobart. The vessel remained partially submerged for a number of years until eventually retreating to the sea floor (Gesner, 1985). In the mid-1980s the wreck, now protected under the Victorian Heritage Act 1995, was rediscovered and its historical and archaeological significance acknowledged as a result of investigations conducted by the Maritime Archaeology Association of Victoria (MAAV) (Gesner, 1985; Harvey, 1986, 1989). These findings were subsequently reported to the Maritime Archaeology Unit (MAU) of the Victoria Archaeology Survey (VAS). In turn, an environmental monitoring program and report was compiled by Coroneos (1991). Today the wreck is located in shallow waters (4-5 m deep) where natural processes and small vessel anchorage are negatively impacting the vessel's structural preservation. In April-May 2012, in accordance with the United Nations Educational, Scientific and Cultural Organisation (UNESCO) Convention on the Protection of the Underwater Cultural Heritage, the first phase of excavation, reburial and in-situ preservation of Clarence was undertaken by the ARC funded AHSPP. During excavations, it was apparent that there was a shallow layer of loose marine sediment overlying a dense clay-rich unit (appearing to have retained marks possibly 2 �produced by bucketing of clay into the hold of the schooner) (Veth et al., 2013) lodged within the vessel structure on top of the schooner's ceiling timbers, between 30-50 cm in depth (Taylor, 2013). A number of finds including cask staves and lids; coir cordage; leather patches and other items were also found within the clay deposit (Veth et al., 2013). Chief investigators Peter Veth, Vicki Richards and project diver Mike Nash, collected cores of the deposit and sediment in and around the wreck. Although clay is proposed to have been a popular form of ballast material in the 19th century (Taylor, 2013), little contemporary or historic material exists regarding its use in Australia. This material makes it difficult to pinpoint particular locations in which clay was collected or how widespread the practice was. If clay-rich sediments are confirmed to be ballast, Clarence could be the first example of a clay ballasted vessel to be located and sampled in the country (Veth et al., 2013). This discovery and questions surrounding future preservation of the wreck stimulated investigations into micro-sedimentary environments and taphonomy associated with the site and the stability of sediments lodged in and around the wreck. Key objectives were to compare mineral signatures in the 'ballast' from clay-rich sources on the seabed and coastal Fig. 1 Short core and grab sample locations in the wreck of the Clarence. (A. Khan) foreshores to confirm the likelihood of clay-rich sediments being ballast. In order to address these questions, sediment samples were collected from the surrounding onshore landscape and analysed using XRD in March 2013 along with samples collected in April-May 2012 from the wreck and adjacent seabed at the Research School of Earth Sciences (RSES), ANU. This analysis was also undertaken to identify the extent of sediment preservation or damage within the wreck. XRD is considered a cheap, fast and relatively effective method for identifying and analysing clay minerals. Although some criticisms have been made in regards to its overall accuracy, if correct precautions are taken it can be a useful tool in identifying clay mineral variations in sediments (Kahle et al., 2002). 3 �Procedures and Methods Sample Sets and Sampling and Preparation Techniques. Initial XRD analysis was carried out on nine sediment samples collected by project divers as part of the Clarence excavations.  Set A: CLI1-0006-9. Samples retrieved as either grab samples or undisturbed cores from the wreck site. Locations are shown in (Fig. 1).  Set B: CLI2-0001-4 and CLI2-0010. Samples retrieved as either grab samples or undisturbed cores from the seabed surrounding the wreck. Locations are shown in (Fig. 1). XRD analysis was then carried out on 15 samples taken from offshore geography directly associated with Port Phillip Bay during a field trip to the area in March 2013. At the Clarence site, the major mechanism by which terrestrial-derived fine grain sediments enter the near shore zone will be run-off plumes after heavy rain. Cliff collapse and direct wave erosion of regolith at cliff bases will make minor contributions (Cardno, 2011). The bedrock and saprolites sampled also approximate the range of deposits likely to be forming seabeds around and beneath the locations where Clarence foundered. The following samples were collected based on the above assumptions.  Set C: SPA1-15. 50-200g of well sorted deposits were collected from five locations across the headlands of Port Arlington and St Leonards (Fig. 2) and stored in clear zip-lock bags. Samples were retrieved from exposures and sections along low cliffed shorelines and one low elevation intertidal clay-pan. Locations and sampling design aimed to produce representative examples of sediments in the complex weathered geology and regolith of Bellarine shorelines, which are actively eroding and releasing sediments into the near shore zone.  SPA1-5 and 12-15 were collected from eroding cliff sections.  SPA 6 and 7 were collected from an intertidal weathered outcrop.  SPA 8, 9 and 10 were collected from Edwards Point, where a salt-pan and mudflat are situated. This site was chosen and sampled as an example of a sediment sink where fine clay-silts have settled from an intertidal water column 4 �behind a bay bar sand barrier. These provide a first-order proxy for sediments/clay mineralogies likely to deposit out of the Port Phillip Bay water column.  SPA11 was sampled from St Leonards Beach, seaward of the adjacent mudflat at Edwards Point. Methods Analysed sediment from Set A was carefully removed from cores in order to avoid contamination of clay-rich deposits with overlying loose marine sediment. Analysed sediment from Set B was sampled at 2cm intervals in order to collect a representative sample of surface and underlying sediments on the sea floor. Therefore, XRD analysis on all Set B samples (except CLI2-0004 and CLI2-0010) Fig. 2 Locations of SPA1-15 sediment samples surrounding Port Phillip Bay. (Google Earth, 2013) was conducted twice per core and conducted on all aspects of the sample, including miscellaneous marine sediment. Analysed sediment from Set C was prepared in order to produce an accurate representation of coastal landscape formations. All remaining sediment from Sets A, B and C were retained in separate storage containers at the RSES, ANU. All sample sets were prepared and analysed using powder XRD and clay separation methods. Powder XRD was carried out with a SIEMENS D501 BraggBrentano diffractometer equipped with a graphite monochromator and scintillation detector, using Cu K-alpha radiation. Bulk samples were milled for 10 min in ethanol with a McCrone Micronizing Mill, and dried at 40°C. Samples were suspended on a side-packed sample holder and analysed from 2 to 70° 2-theta, at a step width of 0.02° 5 �and a scan speed of 1° per minute. Clay separation was performed by the settling method and samples prepared according to the Millipore Filter Transfer Method (Moore and Reynolds, 1997). Clay samples were analysed after Mg-saturation (scan range 242° 2theta, step width 0.02°, scan speed 1°/min), saturation with ethylene glycol (2-32°, 0.02°, 1°/min), and heating to 350°C (2-28°, 0.02°, 1°/min) and to 550°C (2-28°, 0.02°, 1°/min). Results were interpreted using the Bruker AXS software package Diffracplus Eva 10 (2003) for identification, and Siroquant V3 for quantification (using the bulk scan). Results Results are shown in Tables 1, 2 and 3 and Fig. 3. Table 1 represents results from Set A, collected from within the wreck. Table 2 represents results from Set B, collected from the sea floor surrounding the wreck site. Table 3 represents results from Set C, collected from surrounding coastal geologies in Port Phillip Bay. Fig. 3 illustrates variations in mineralogical compositions in Sets A and B, specifically with regards to kaolinite, plagioclase and clinopyroxene quantities. Small quantities of vermiculite were present throughout all sample sets: Set A contained an average of 0.50 ± 0.03%, one sample in Set B contained 0.4% vermiculite and three samples in Set C contained traces of the mineral (SPA5, 0.1%, SPA7, 0.4% and SPA 14, Fig. 3 Mineralogical percentages of kaolinite, plagioclase and 0.6%). Calcite and aragonite clinopyroxene in Sets A and B. (A. Zubrzycka) were not well represented in Set A, however CLI-0009, contained 5.1% calcite and 6.2% aragonite. Quartz, likely to be associated with loose sand particles from the surrounding seabed, was abundant in Sets A (Mean (M) = 29.9 ± 6.0%) and B (M = 27.5 ± 1.0%). Sets A and B contained halite that can be attributed to trace levels of salt water retained in samples during preparation. Small quantities of illite/smectite were present in the 6 �majority of Set B samples (M = 0.4 ± 0.3%) while only one sample in Set A, CLI-0005, contained the clay mineral (5.6%). The presence of clinopyroxene was unique to Set A samples CI10008 (13.8%) and CLI10009 (7.7%), which were collected in direct association with clay-rich deposits in the wreck (Fig. 3). Large quantities of kaolinite were present in Set A (M = 43.7 ± 16.7%). In comparison, Set B samples were clay poor, containing only trace levels of kaolinite (M = 1.1 ± 0.2%) (Fig. 3). Plagioclase was present in both Set A and B with Set A containing an average of 6.8 ± 7.9% and Set B an average of 2.7 ± 0.5% (Fig. 3). Calcite and aragonite were found in abundance in Set B (M = 51.2 ± 2.5% and 13.5 ± 0.8%, respectively). All Set C samples, except SPA11 (beach sand), were clay rich and contained little to no traces of feldspars, such as plagioclase (0%) and K-feldspar, which was only present in SPA3 (1.8%). In comparison, Set A contained an average of 3.3 ± 2% K-feldspar. Only one sample in Set C, SPA10, contained aragonite (15.3%) probably associated with a midden deposit or activity associated with higher sea levels or storm surges. Clay fractions from SPA1 and 8 were dominated with illite/muscovite (27.4% and 32.9%, respectively). Clay fractions from SPA4 (74.3%), SPA5 (89.3%), SPA6 (85.6%) and SPA15 (87.8%) were dominated by kaolinite. SPA7 contained the largest quantity of kaolinite at 96.3%. Overall, the mean quantity of kaolinite within Set C was 40.1 ± 37.8% (as opposed to M = 43.7 ± 16.7% in Set A and 1.1 ± 0.2% in Set B). SPA2 was dominated by goethite (52.6%), which was not present in Set A or B. Set C contained a mean average of 24.8 ± 25.3% quartz. This average was reached by excluding SPA11, a sample of beach sand containing 97.7% quartz. Average quartz quantities in Set C including SPA11 is 29.7 ± 30.8%. Anatase was present in SPA4 (3.9%), SPA5 (4.6%), SPA6 (2.9%) and SPA 7 (2.7%), all collected from low lying cliff sections. Because a number of samples, especially those within data sets A and B contained halite and/or calcite inaccurate results relating to quantification of minerals and clays in the final stages of data analysis were present. In order to account for these irregularities total clays with and without these minerals have been included in all tables. 7 �Discussion The hypothesis that clay deposits accumulated in Clarence after becoming submerged in its present position as a result of slack water “fines settling” within the vessel is inconsistent with data accumulated from the XRD analysis of all samples. This can be observed by comparing mineralogical variability and clay quantities from all sample sets, especially those in Set A and B. Some of the most significant results came from samples CLI1-0008 and CLI1-0009, collected from clay-rich deposits thought to be ballast. These were the only collected and analysed samples to contain clinopyroxene. All samples in Set A contained high percentages of kaolinite, however, CLI1-0008 and 0009 contained significantly less kaolinite (21.1% in CLI1-0008 and 32.3% in CLI1-0009) than analysed samples collected from the wreck, which contained an average of 55.1 ± 6.5% kaolinite (Fig. 3). CLI1-0008 and 0009 also contained higher quantities of plagioclase and K-feldspar than other samples (see Table 1 and Fig. 3). Thus, clay-rich sediment, thought to be ballast, found near the schooner's ceiling planking contains a unique mineralogical composition compared to other sampled sediments within the wreck structure. The hypothesis that clay-rich sediments may have accumulated on the wreck over time, taking on the appearance of clay ballast, is also unlikely based on results from Set B. If clay rich sediments derived from the surrounding landscape had settled on the wreck via storm surges or tidal and current activity, it is likely that similar clay minerals would be present on the adjacent seabed. However, low quantities of kaolinite and a complete lack of clinopyroxene in Set B suggest that this is not the case (Fig. 3). XRD results from Set C also indicate that there is no mineralogical relationship between sediments collected from surrounding coastal geologies and clay-rich sediments found within the wreck. In regards to the stability of sediments within the wreck, comparing mineralogical data from sample Sets A and B indicates that bioturbation and damaging ocean currents have had minimal effect on what may be in situ clay sediments directly associated with the wreck. This can be observed via the presence of calcite in Set A where the mineral is only present in CLI-0009 (5.1%). However, biased sample 8 �preparation in the lab may be associated with this result, i.e. shell fragments and other material being removed from Set A and B samples prior to milling. Conclusion The wreck of the Clarence can provide researchers with valuable information on the history of shipbuilding and ballast use in Australia during the early to mid-19th Century. The location of the wreck also carries the potential to inform researchers of the detrimental effect environmental and anthropogenic activity may have on the survival of the Clarence and other wrecks in similar locations. The discovery of clay-rich sediment during the 2012 excavation gave researchers a unique opportunity to investigate both of these questions using identical methodologies. Results from XRD analysis successfully differentiated samples collected from the seabed adjacent to the wreck, clay-rich sediments collected within the wreck and sediment collected from the surrounding coastline. This suggests that clay-rich sediments are unlikely to have been transported to the wreck via factors such as storm surges or ocean currents carrying fine grained sediments from the adjacent coastline. Findings suggest that clay sediment within the Clarence shipwreck is likely to be clay ballast or another form of clay material, emplaced in the vessel at some point during its working life. Results were further emphasised due to the presence of clinopyroxene, plagioclase and kaolinite in samples directly associated with clay-rich deposits found near the hull of the vessel. The survival of clayrich sediment within the wreck suggests that although natural and anthropogenic activity can have a detrimental effect on the preservation of underwater cultural heritage, it is possible for archaeologically significant material to be well preserved within these contexts. In order to reach a more definitive conclusion on the likelihood that clay-rich deposits are indeed ballast, more data from Australian built wrecks and archival material is required. It is also suggested that further comparative analysis of clay-rich sediments found on the wreck and the surrounding landscape be undertaken using alternative analytical methods. 9 �References Cardno, 2011. Sediment Transport Modelling – Great Sands, Port Phillip. RM2271/LJ5518 Version 1.0. Report prepared for Port of Melbourne Corporation, 6 March 2011, Cardno Victoria Pty Ltd, Collingwood, Victoria. Coroneos, C., 1991. Historical Shipwreck, The Clarence (1841-1850) Conservation Plan. Unpublished report submitted to the Victoria Archaeological Survey, Melbourne, Victoria. Gesner, P., 1985. Clarence Report: Historical Documentation. Unpublished report submitted to the Victorian Archaeological Survey, Melbourne, Victoria. Harvey, P. 1986. A Pre-disturbance Survey of the Shipwreck Clarence in Port Phillip. Unpublished report submitted to the Victorian Archaeological Survey, Melbourne, Victoria. Harvey, P. 1989. Excavation of the Shipwreck Clarence: Port Phillip Bay, October 1987. Unpublished report submitted to the Victorian Archaeological Survey, Melbourne, Victoria. Kahle, M., Kleber, M. and Jahn, R., 2002. Review of XRD-based quantitative analyses of clay minerals in soils: The suitability of mineral intensity factors. Geoderma, Vol. 109 (3-4): 191-205. Moore D. M., and Reynolds, R. C., 1997. X-ray Diffraction and the Identification and Analysis of Clay Minerals. 2nd edition, Oxford University Press. Taylor, P., 2013. Shipwrecks: A Practical Guide to Research and Discovery. Scuttlebutt Press, Australia. Veth, P., Philippou, C., Richards, V., Staniforth, M., Rodrigues, J., Khan, A., Creagh, D., Viduka, A., Barham, A., MacLeod, I., and Harvey, P., 2013. The Australian Historic Shipwreck Preservation Project 2012: First report on the background, reburial and insitu preservation at the Clarence (1841-50). Bulletin of the Australasian Institute for Maritime Archaeology, Vol. 37: 1-19. 10 �Biography Adele Zubrzycka is a Masters of Archaeological Science candidate at the Australian National University. Her Masters thesis examined built structures and material culture associated with the first Presbyterian mission station established in Vanuatu (1848). Her research interests lie in historical archaeology with an emphasis on the colonial period in South Asia, specifically the production and trade of indigo in India. Anthony Barham is a geoarchaeologist by training with a specific interest in landscape stratigraphy and archaeological site environments. His research spans Regolith and Soil Science, Quaternary Science and Archaeology. He has a long-standing interest in the Holocene geomorphological development and human occupation record of Australian tropical coastlines, especially regional syntheses of archaeological and palaeoenvironmental records in Torres Strait, and recently on the Kimberley coast of Western Australia (WA). Current research includes evaluating impacts of past tsunami events (and cyclone storm surges) in WA using archaeological data sets. Dr Ulrike Troitzsch is the X-ray Diffraction Laboratory Manager at the Australian National University, Canberra. Her thesis was based on the crystal structure and thermodynamic properties of titanite solid solution Ca(Ti,Al)(O,F)SiO4. Her research interests lie in experimental and metamorphic petrology, mineralogy, crystal chemistry, solid solutions, ceramics granites and migmatites crystal structure determination and refinement. 11 �CLI1-0005 CLI1-0006 CLI1-0007 CLI1-0008 CLI1-0009 Location Close to Near keelson, Centre ceiling stern end wreck planking near foremast stump of Close to Near ceiling ceiling planking, bow planking near end foremast stump Goodness of 2 fit X 3.16 3.80 3.31 4.09 3.55 Quartz 34.9 22.5 25.2 36.6 30.4 Plagioclase - 3.9 2.3 20.2 7.9 K-feldspar - 3.6 3.2 4.8 5.0 Halite 1.2 5.9 2.5 0.5 0.6 Calcite - - - - 5.1 Illite/smectite 5.6 - - - - Vermiculite - 0.2 0.7 0.6 0.8 Aragonite - - - - 6.2 Gypsum - - - - 2.1 Illite/muscovite 10.4 7.0 5.5 2.4 1.9 Kaolinite 47.9 56.9 60.6 21.1 32.3 Clinopyroxene - - - 13.8 7.7 Total 100 100 100 100 100 Total clay 63.9 64.1 66.8 24.1 35.0 Total clay w/out carbonates or halite 64.7 68.1 68.5 24.2 39.7 Minerals Table 1 CLI1 samples collected from the Clarence wreck site, April/May 2012. (A. Zubrzycka) 12 �CLI20001 0-2 cm CLI2CLI-0002 0001 2-4 cm CLI20003 0-2 cm CLI20003 2-4 cm CLI20004 CLI20010 Location Stern end, starboard side. Stern end, starboard side. Bow end, Stern starboard end, starboard side. side. Bow end, starboard side. Bow end, Bow end, port side. port side. Goodness of fit X2 2.76 2.55 2.52 2.43 2.47 2.29 2.38 Quartz 28.5 30.6 28.4 28.7 25.4 24.8 26.1 Plagioclase 2.5 3.0 3.8 2.7 2.3 2.7 2.2 Halite 1.3 0.6 1.2 1.0 1.6 0.9 1.1 Calcite 51.3 48.7 48.2 49.3 53.6 54.7 52.5 Dolomite 1.6 1.1 1.1 1.2 1.0 1.0 1.2 Aragonite 12.5 12.5 14.2 14.7 13.6 13.3 13.9 Vermiculite - 0.4 - - - - - Illite/muscovite 1.3 1.0 1.5 0.5 1.2 1.0 1.8 Illite/smectite - 1.0 0.5 0.3 0.4 0.3 0.3 Kaolinite 1.0 1.1 1.1 1.6 0.9 1.3 0.9 Total 100 100 100 100 100 100 100 Total Clay 2.3 3.5 3.1 2.4 2.5 2.6 3.0 Total clay w/out carbonates and halite 6.9 9.4 8.8 7.1 8.3 8.6 9.6 Minerals Table 2 CLI2 samples collected from adjacent sea floor associated with the Clarence wreck site, April/May 2012. (A. Zubrzycka) 13 �SPA1 SPA2 SPA3 SPA4 SPA5 SPA6 SPA7 SPA8 SPA9 Goodness of fit X2 SPA1 SPA1 SPA1 SPA1 SPA1 SPA1 0 1 2 3 4 5 2.97 2.55 3.39 3.57 4.85 4.51 5.15 4.32 4.07 3.42 3.04 3.89 3.99 4.59 4.51 Minerals Quartz 44.1 28.1 64.9 - 0.5 0.3 - 14.9 13.9 25.9 97.7 74.4 55.4 17.6 8.4 K-feldspar - - - - - - - - - - - Goethite 10.7 52.6 - 1.6 3.4 7.4 - - - - - - 10.9 14.9 - Hematite - - - 14.8 3.1 - - - - 2.3 2.8 - - - Halite - - - 5.4 1.8 0.7 0.6 14.7 42.8 9.4 - - - - 1.9 Calcite 14.7 4.4 6.5 - - - - 1.8 - 11.0 - - - - - Aragonite - - - - - - - - - 15.8 - - - - - Gypsum - - 1.6 - - - - 1.3 3.7 1.5 - 1.1 0.7 - - Smectite - 9.6 - - - - - - - - - - - - - - - - 0.1 - 0.4 - - - - - - 0.6 - Vermiculite - - 1.8 - - Illite/ muscovite 27.4 3 20.8 - 0.30 - - 32.9 16.8 18.8 - - - 1.9 1.9 Illite/ smectite - - - - - - 17.5 10.6 7.5 - - - - Kaolinite 3.1 2.3 4.4 74.3 89.3 85.6 96.3 16.9 12.2 10.1 - 21.7 33.0 65.0 87.8 Anatase - - - 3.9 - Total 100 100 100 100 100 Total Clay 30.5 14.9 25.2 74.3 89.7 85.6 96.7 67.3 39.6 36.4 0.0 Total clay 35.8 15.6 27 w/out carbonates and halite 4.6 - 2.9 2.7 - - - - - - - 100 100 100 100 100 100 100 100 100 78.5 91.3 86.2 97.3 80.6 69.2 57.1 0.0 100 21.7 33.0 67.5 89.7 22.3 33.0 67.5 91.4 Table 3 SPA samples collected from geology surrounding Port Phillip Bay, March 2013. (A. Zubrzycka) 14 - � Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Session 7: Preservation and Conservation of Wet Archaeological Materials and Site Management Subject The topic of the resource Interview with Session 7 chairs Vicki Richards and Jon Carpenter and links to the papers presented in the session. Description An account of the resource This session will focus on in-situ preservation and conservation management issues, conservation analyses and treatments, and applied conservation research of archaeological materials from freshwater, marine and wet terrestrial sites. The main purposes of this session are to encourage the exchange of ideas and practices as well as the development of conservation networks throughout the region. Presentations, posters and workshops are invited that address any of the following areas: • In situ preservation of marine archaeological materials, including reburial practices • Conservation management of shipwreck sites, including on-site monitoring • Conservation treatment case studies • Research into the analysis and treatment of wet archaeological materials • Review of the status of wet archaeological conservation programs in the Asia Pacific region • Development of collaborative conservation research and treatment programs Suggestions for additional topics are welcomed by the session organizers. Creator An entity primarily responsible for making the resource Vicki Richards and Jon Carpenter Document A resource containing textual data. Note that facsimiles or images of texts are still of the genre text. Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Tracking environmental and historical footprints on Clarence: Comparative XRD analysis of clay-rich sediment samples from a 19th century wreck site in Port Phillip Bay, Victoria, Australia Description An account of the resource Little is known about shipbuilding in Australia in the early to mid 19th century. Under the Australian Research Council (ARC) funded Australian Historic Shipwreck Preservation Project (AHSPP) (www.ahspp.org.au), underwater excavations were carried out in April- May 2012 on the historic trading schooner Clarence, wrecked in shallow waters at Port Phillip Bay, Victoria in September 1850. During excavations, cores collected by lead investigator Peter Veth and principle investigator Vicki Richards were found to contain clay-rich sediment, thought to be ballast. This discovery stimulated investigations of the micro-sedimentary environments and taphonomy associated with the vessel, especially fine-grain sediment supply to the wreck and current and tidal influences on the stability of sediments lodged in and around the site. In order to address these questions, sediment samples were collected from the wreck, seabed and adjacent shorelines. Clay fractions were analysed at the Australian National University (ANU) using X-Ray Diffraction (XRD). Key objectives were to compare mineral signatures in the 'ballast' from clay-rich sources on the seabed and coastal foreshores possibly incorporated as the vessel foundered. Results successfully differentiate a) individual samples by seabed location and b) “ballast” samples in the wreck structure from sampled points around the wreck. The findings suggest that fine sediment within the Clarence shipwreck is likely to be clay ballast, emplaced at some point during the schooner's working life. The results also inform questions regarding the longer-term conservation of Clarence and similar wrecks located in Australian and Southeast Asian shallow-water settings. Creator An entity primarily responsible for making the resource Adele Zubrzycka Anthony J. Barham Ulrike Troitzsch, in Van Tilburg, H., Tripati, S., Walker Vadillo, V., Fahy, B., and Kimura, J. (eds.) Date A point or period of time associated with an event in the lifecycle of the resource 5/15/2014 Asia-Pac Session 7 2014 https://apconf-much.org/proceedings/files/original/2c9cbfa92956afba174668da5ca9fedf.pdf 77bf4dab13ec4aff60c85768aaa97573 PDF Text Text Research on the removal of calcareous and iron concretions from marine finds Zhang Zhiguo, Ma Qinglin, Li Naisheng, and Tian Xingling Department of Conservation Science and Technology for Underwater Cultural Relics Center for Cultural Relic Restoration and Training Chinese Academy of Cultural Heritage No. 2 Gao Yuan Street, Chao Yang District, Beijing 100029 China Email: zzgwys@126.com Liu Wei University of Science and Technology, Beijing China Abstract In recent years, several shipwrecks have been found in the South China Sea, such as Huaguang Jiao I and South China Sea I, shipwrecks from the Southern Song Dynasty (12-13c AD) and Nan’ao I, a wreck from the Ming Dynasty (14-17c AD). Many ancient archaeological iron objects were found the site. Usually, calcareous and iron concretions exist on these iron objects and some iron objects are concreted together very tightly. This paper discusses methods to remove calcareous and iron concretions from archaeological iron objects found from the sea and separation methods for the concreted iron objects recovered from the Huaguang Jiao I and South China Sea I shipwrecks. Key words: Huaguang Jiao, South China Sea I shipwreck, Iron objects; Calcareous; Iron concretions; Removal techniques Introduction The most striking feature of iron corrosion in a marine environment is the formation of thick concretions. Concretions form on iron buried beneath the seabed and on that exposed to seawater. In both cases the concretion is formed by the iron corrosion products interacting with material adjacent to the iron. Iron is not a biologically toxic material and any iron immersed in seawater is rapidly colonized by marine organisms. These organisms build up a layer of skeletal material, predominantly calcium carbonate (CaCO3). The subsequent diffusion of iron II ions (Fe2+) and iron III ions (Fe3+) from the 1 �underlying corroding iron produces chemical changes in this biological material (North, 1976). In the concretion, Fe2+ ions interchange with calcium ions (Ca2+) in the CaCO3, to produce ferrous carbonate or siderite (FeCO3). Some of the CaCO3 is also dissolved by the hydrogen ions (H+) forming calcium bicarbonate [Ca(HCO3)2], which causes the pH of the solution to increase. The increasing pH then results in the gradual precipitation of Fe2+ and Fe3+ as oxides, hydrated oxides and hydroxy chlorides. These fill holes and pores in the concretion and so form an iron cementing matrix to replace the original calcite matrix, which is slowly dissolving. Under the concretion, in areas of low oxygen content, reactions between iron ions and sulphide ions (S2-) ions produced by sulphate reducing bacteria result in the formation of iron (II) sulphides (FeS) and elemental sulphur (S). The end result of these processes is that the inner concretion becomes a replica of the marine growth but with the CaCO3 of the marine organisms virtually entirely replaced by iron corrosion products (North, 1976). The outer layer of the iron concretions is approximately the same composition as the marine growth on inert materials. The major differences are the presence of up to 2% iron and small, but significant amounts of inorganic CaCO 3. When iron is continuously buried beneath the seabed, negligible marine growth occurs but a hard concretion can still be formed provided the seabed material contains CaCO 3. The mechanism here appears to be basically the same as for exposed iron. As the iron-rich acidic solution diffuses into the surrounding seabed material it dissolves some CaCO3 and precipitate iron compounds which act as a binding cement. Further out from the object the previously dissolved calcium reprecipitates, due to increasing pH, and forms a second cementing layer. As a result any material in the seabed next to the corroding iron is incorporated into the concretion. Magnetite (Fe3O4) is the main iron oxide component of buried concretions compared with iron oxy hydroxides (FeOOH) and haematite (Fe2O3) in exposed concretions (North, 1987a). The concretions from the Batavia shipwreck site in Australia mainly contained FeOOH, Fe3O4, FeCO3 and iron hydroxy chlorides (FeOCl), minor constituents were CaCO3, quartz (SiO2), FeS and S and sometimes contained traces of sodium chloride (NaCl) and gypsum (CaSO4.2H2O) (North, 1976). North (1982) compared the chemical compositions of concretion and iron corrosion products from the Day Dawn shipwreck 2 �site in Australia, the concretions consisted of 46.1% iron (Fe), 0.34% sodium (Na), 7.9% calcium (Ca), 0.33% magnesium (Mg), 2.2% SiO2 and less than 0.05% chlorine (Cl), but the iron corrosion products consisted of 60.8% Fe, 0.06% Na, 0.11% Ca, 0.03% Mg and 6.1% Cl (North, 1982). Concretions found within marine sediment, where oxygen is relatively scarce, contain higher proportions of lepidocrocite (γ-FeOOH), Fe3O4, and the magnetic sulphide, pyrrhotite (Fe1-xS). Other compounds, which are unstable under atmospheric conditions, and thus difficult to identify, may also by present (Cronyn, 1990). The main method of concretion removal is by mechanical methods, such as toothpick, dental drill, riveting gun, hammer and sand-blasting machine (Hamilton, 1999; Mardikian and David, 1996; North 1987b; Rees-Jones, 1972). Chemical methods, such as 20% phosphoric acid (Rees-Jones, 1972) and hot soda baths (Pearson, 1972), have been used, especially for seriously corroded fragile iron, but concreted iron objects cannot be soaked for a long time. Liquid nitrogen (MacLeod, 1987) and electrolytic methods (Montlucon, 1986) can also be used for concretion removal. The liquid nitrogen method is effective in removing thick calcium carbonate layers on iron surfaces. Hydrogen produced by the electrolytic method may cause damage to the surfaces of ancient iron objects. The concretions on some marine iron recovered from three shipwrecks excavated from the South China Sea, HuaguangJiao I and South China Sea I, wrecks from the Southern Song Dynasty (12-13c AD) and Nan’ao I, a wreck from the Ming Dynasty (1417c AD), were analysed using multiple scientific techniques to determine the composition and structure of the concretions. The concretions from the three wrecks are composed primarily of two different types; calcareous/iron concretions or coral and siliceous concretions. The different types of concretion from the three wrecks were comparatively analysed. The results indicated that the concretions from South China Sea I contain calcareous and siliceous concretions, mainly SiO2, mixed calcareous concretions, FeS2, and FeCO3. And concretions from HuaguangJiao I were analogous to those from Nan’ao I except the composition of the iron concretions from the former consisted primarily of Fe3O4, goethite (α-FeOOH), lepidocrocite (γ-FeOOH), Fe2O3 and akaganeite (β-FeOOH), while FeS, FeCO3 and β-FeOOH were the main minerals present in the Nan’ao I iron concretions (Liu et al., 2011). This paper discusses methods 3 �to remove calcareous and iron concretions from marine archaeological ancient iron objects and tests some separation methods for the concreted iron objects from the HuaguangJiao I and South China Sea I shipwrecks. Results and Discussion Removal of the Calcareous Concretions by Chemical Methods Figure 1 shows the white calcareous concretions on the iron object, HTQ-9 from the HuaguangJiao calcareous I concretions shipwreck. are The usually composed of two layers, an outer and inner layer. Two samples of the different layers were collected using a scalpel. The outer Fig. 1 Iron object (HTQ-9) from the HuaguangJiao white surface layer consisted of calcite I shipwreck. (Z. G. Zhang). (Mg0.1Ca0.9CO3) and aragonite (CaCO3) and the inner white layer consisted of kutnahorite (Ca1.11Mn0.89 (CO3)2 and CaCO3. Figures 2a and 2b show the XRD spectrums of the outer and inner layer samples. The calcareous concretions of two layers are both very hard, and the inner layer is harder than outer one. About 0.4g of the white calcareous concretion, removed from the outer and inner layer of iron object HTQ-9, was soaked in a 10% EDTA disodium salt solution (EDTA-2Na), pH value was about 10. Figure 3 shows the transformation process of the concretion sample. The sample had completely dissolved after 102 hours. This experiment demonstrates that 10% EDTA-2Na can remove these types of white calcareous concretions present on this marine iron object. Removal of the Iron Concretions by Chemical Methods The iron object of HTQ-17 from the HuaguangJiao I shipwreck was sectioned into five sub-samples. The size of each sample was about 3.0 square centimeters. The red brown iron concretion on their surface was analysed by XRD. Figure 2c shows the XRD spectrum. The analysis result indicated the concretion mainly consisted of β-FeOOH, γFeOOH, Fe3O4 and α-FeOOH. Five solutions; 5% oxalic acid, 10% oxalic acid, 9.35% aminoacetic acid, 9.35% aminoacetic acid sodium salt and 9.35% mercaptoacetic acid sodium salt, were tested to dissolve the red brown iron concretions on five samples of 4 �HTQ-17. Figure 4 shows the transformation of the red brown iron concretions of HTQ17 in 9.35% mercaptoacetic acid sodium salt. The results of the experiment demonstrated that the dissolution rate of the red brown iron concretions in each solution in decreasing order was: 9.35% mercaptoacetic acid sodium salt, 9.35% aminoacetic acid, 9.35% aminoacetic acid sodium salt, 10% oxalic acid, 5% oxalic acid. So the 9.35% mercaptoacetic sodium salt was the best solution to dissolve the iron concretions. Removal of the Iron Concretions by Mechanical Methods Laser blasting, sandblasting and ultrasonic cleaning methods are effective techniques to remove concretions from marine iron objects (Hamilton, 1999). However, the laser method has the disadvantage that the power is difficult to control; it is an expensive technique and is not suitable for large areas and/or thick concretion layers. Sandblasting is appropriate for the more fragile iron objects with thin concretion layers. Ultrasonic cleaning, such as an ultrasonic dental tool, is useful for deconcreting small areas covered in thin concretion layers, which are not particularly hard and the power is easily controlled. Mechanical and chemical methods are commonly used in combination to remove concretions from marine iron objects. Figure 5a shows a concreted iron nail recovered from the South China Sea I shipwreck. The concretion was removed using a combination of mechanical and chemical techniques, i.e. a solution of EDTA-2Na in conjunction with a chisel and scalpel were used to remove the concretion from this object. Figure 5b shows the iron nail after concretion removal. Separation of a Group of Concreted Iron Objects Figure 6a shows a group of four concreted iron objects, HTQ-2 recovered from the HuaguangJiao I shipwreck. Some mechanical tools, such as an electric drill, an engraver, a chisel and a small hammer were used to mechanically separate the iron objects. Special care was taken during the separation process to avoid any fracture or breakage. When the electric drill was used for separation, the appropriate diameter drill bit was chosen and the power should be controlled according to the extent of corrosion and the distance between the concreted iron objects. Figure 6b shows the four iron objects after separation. 5 �Conclusion This paper presented some experimental results on a variety of removal methods for calcareous and iron concretions from marine archaeological ancient iron objects. Based on the analytical data, 10% EDTA-2Na can remove the white calcareous concretions on marine iron objects and 9.35% mercaptoacetic acid sodium salt solution can dissolve the red brown iron concretions successfully. Commonly combinations of mechanical and chemical techniques can remove block concretions on marine iron objects and separate groups of concreted iron objects. Mechanical techniques are still the most common and reliable method for concretion removal. 6 �Fig. 2 XRD spectrum of HTQ-9 (a = outer layer; b = inner layer) and HTQ-17 (c). (Z. G. Zhang) 3a 3b 3c 3d Fig. 3 Transformation of calcareous concretions from HTQ-9 in 10% EDTA disodium salt after (a) 0 hours, (b) 6.5 hours, (c) 54 hours, (d) 102 hours. (Z. G. Zhang) 7 �Fig. 4 Transformation of the red brown iron concretions from HTQ-17 in 9.35% mercaptoacetic acid sodium salt after (a) 24 hours, (b) 72 hours, (c) 144 hours. (Z. G. Zhang) Fig. 5 Iron nail from the South China Sea I shipwreck. (a) Before deconcretion, (b) After concretion removal. (Z. G. Zhang) Fig. 6 Concreted group of iron objects, HTQ-2 from the HuaguangJiao I shipwreck (a) Pre-separation, (b) After separation. (Z. G. Zhang) 8 �Acknowledgements We would like to thank Mr. Qiu Gang, Director of Hainan Museum, who supplied the marine iron samples. We would also like to thank Prof. Zhan Changfa and Dr. Shen Dawa for their assistance with the analysis and research. This research project was financially supported by the Chinese Academy of Cultural Heritage (CACH). References Cronyn, J. M., 1990. The Elements of Archaeological Conservation. Routledge Press, Britain, 181. Hamilton, D. L., 1999. Methods of Conserving Archaeological Material from Underwater Sites. Nautical Archaeology Program. Department of Anthropology. Texas A&M University. College Station, Texas, 54-55. Liu, W., Wang, J. L., and Zhang, Z. G., 2011. Scientific analysis of the concretion on ancient marine iron recovered from three shipwrecks in South China Sea. Journal of National Museum of China, Vol. 2: 145-156. Mardikian, P., and David, R., 1996. Conservation of a French pistol from the wreck of Le Cygne (1808). Studies in Conservation, Vol. 41: 161-169. MacLeod, I. D., 1987. Conservation of corroded iron artefacts - new methods for on-site preservation and cryogenic deconcreting. International Journal of Nautical Archaeology and Underwater Exploration, Vol. 16 (1): 49-56. Montlucon, J., 1986. Electricity: A new implement in archaeology. In J. W. Foster and O. S. Sheli (Eds.), 17th Conference on Underwater Archaeology. Sacramento, California, January 8-12, 1986, Facsimile Reprint by Coyote Press: 75-78. North, N. A., 1987a. Corrosion of metals. In C. Pearson (Eds.), Conservation of Marine Archaeological Objects, London, Butterworths: 77-78. North, N. A., 1987b. Conservation of Metals. In C. Pearson (Eds.), Conservation of Marine Archaeological Objects, Butterworths, London, 209-211, 223-227. North, N. A., 1982. Corrosion products on marine iron. Studies in Conservation, Vol. 27: 75-83. North, N. A., 1976. Formation of coral concretions on marine iron. International Journal of Nautical Archaeology and Underwater Exploration, Vol. 5 (3): 253-258. 9 �Pearson, C., 1972. The preservation of iron cannon after 200 years under the sea. Studies in Conservation, Vol. 17: 102. Rees-Jones, S. G., 1972. Some aspects of conservation of iron objects from the sea. Studies in Conservation, Vol. 17: 39-43. Biography Zhiguo Zhang received his BSc (2001) and MSc (2004) in Chemistry from Shandong University and Tsinghua University, respectively and attained a PhD (2011) in history of science and technology from the University of Science and Technology, Beijing, China. His research field comprises the analysis and conservation of museum objects and the protection of marine cultural relics, such as ancient Chinese pigments, metals, stone, and wooden shipwrecks. Since 2004, he has worked on the conservation and research of ancient objects at the Chinese Academy of Cultural Heritage (CACH) in Beijing. 10 � Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Session 7: Preservation and Conservation of Wet Archaeological Materials and Site Management Subject The topic of the resource Interview with Session 7 chairs Vicki Richards and Jon Carpenter and links to the papers presented in the session. Description An account of the resource This session will focus on in-situ preservation and conservation management issues, conservation analyses and treatments, and applied conservation research of archaeological materials from freshwater, marine and wet terrestrial sites. The main purposes of this session are to encourage the exchange of ideas and practices as well as the development of conservation networks throughout the region. Presentations, posters and workshops are invited that address any of the following areas: • In situ preservation of marine archaeological materials, including reburial practices • Conservation management of shipwreck sites, including on-site monitoring • Conservation treatment case studies • Research into the analysis and treatment of wet archaeological materials • Review of the status of wet archaeological conservation programs in the Asia Pacific region • Development of collaborative conservation research and treatment programs Suggestions for additional topics are welcomed by the session organizers. Creator An entity primarily responsible for making the resource Vicki Richards and Jon Carpenter Document A resource containing textual data. Note that facsimiles or images of texts are still of the genre text. Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Research on the removal of calcareous and iron concretions from marine finds Description An account of the resource In recent years, several shipwrecks have been found in the South China Sea, such as Huaguang Jiao I and South China Sea I, shipwrecks from the Southern Song Dynasty (12-13c AD) and Nan’ao I, a wreck from the Ming Dynasty (14-17c AD). Many ancient archaeological iron objects were found the site. Usually, calcareous and iron concretions exist on these iron objects and some iron objects are concreted together very tightly. This paper discusses methods to remove calcareous and iron concretions from archaeological iron objects found from the sea and separation methods for the concreted iron objects recovered from the Huaguang Jiao I and South China Sea I shipwrecks. Creator An entity primarily responsible for making the resource Zhang Zhiguo Ma Qinglin Li Naisheng Tian Xingling Liu Wei, in Van Tilburg, H., Tripati, S., Walker Vadillo, V., Fahy, B., and Kimura, J. (eds.) Date A point or period of time associated with an event in the lifecycle of the resource 5/15/2014 Asia-Pac Session 7 2014 https://apconf-much.org/proceedings/files/original/346e893b23bdfe7241e4cb16b4c49dc5.pdf 74c9e8dce5178cff8829f0646a84a1c5 PDF Text Text Study of the corrosion of copper coins from the wreck of “The South China Sea No.1” Xing-ling Tian, Nai-sheng Li, and Zhi-guo Zhang Department of Conservation Science and Technology for Underwater Cultural Relics, Center for Cultural Relic Restoration and Training Chinese Academy of Cultural Heritage Beijing, 100029 China E-mail: Tiantian1278[at]sina.com Hengyang University of Science and Technology Beijing, 100029 China Abstract. The South China Sea No.1 is the wreck of the longest, largest and most preserved shipwreck site in China. It is a classic example of bireme construction and navigational technology. The artefacts located on the site may provide many secrets of the Silk Road on the sea. Therefore, the archaeological value is greater than its economic value. In order to know more about the craftwork and the state of the coppers in this wreck, this paper will examine the concretion and corrosion on the surface of copper samples obtained from the upper layer of South China Sea No. 1. The samples were analysed with metallographic microscopy, 3D video microscopy, X-ray diffraction (XRD),X-ray fluorescence（XRF) and scanning microscopy (SEM-EDS). The results show that the copper coin is tin-lead bronze, and the content of Cu is about 94%. The corrosion is mainly Cu2(OH)3Cl, Cu2O, Cu(OH)2, Cu(OH)Cl and Cu(SO4)2. The concretion on the surface of the copper coin is rich, but the matrix becomes thinner. Lead (Pb) is scattered freely in the matrix. Tin (Sn) is high in the corrosion layer, which shows that some Cu has corroded. The electrochemistry of the corrosion was controlled by oxygen depolarization. Selective corrosion occurred between Cu and Sn, and the effect of Clsped up the rate of corrosion in the electrochemical reaction. The results of the study can provide a reference for the protection of the copper artefacts excavated from South China Sea. Key words: The South China Sea No.1, copper coin, archaeology 1 �Introduction Due to being in an underwater environment, undersea bronze has its own corrosion characteristics and corrosion products, which vary from bronze relics found on the land. With the high-speed development of underwater archaeology abroad, more and more resources have been put into the study of undersea relics in China. Internationally, several research projects studying the characteristics, composition, theory of corrosion and composition of the corrosion products in undersea bronzes have been conducted (Beccaria et al., 1982; Gettens, 1933; MacLeod, 1991;MacLeod, 1982;Scott, 2002). Gettens (1964), for example, identified cuprous sulphide (Cu2S) and digenite (Cu18S)in the corrosion products on copper nails recovered from a shipwreck in the Mediterranean. Copper (II) sulphate (CuS)was identified by XRD on a fragile black-blue bar from the wreckage of Herminie. According to studies of the corrosion products on undersea bronze by MacLeod (1985), North(1987) and Nord(1993),copper oxide(Cu2O), cuprous chloride (CuCl), chalcanthite (CuSO4·5H2O), brochatite (Cu4SO4(OH)6), lead carbonate (PbCO3), lead sulfate (PbSO4), stannic oxide (SnO2), and CuS are also common corrosion products. Currently, research on the conservation of bronze artefacts in China is still lacking. Despite the development of underwater archaeology internationally, more and more bronze artefacts are being recovered but domestically, the question of how to protect them is still a problem. Researchers are therefore using The South China Sea No.1 as a case study to research the conservation of bronze relics. This site provides a typical sample for the study of ancient Chinese shipbuilding technology and marine technology. The associated artefacts can also potentially unlock the key to many secrets of the marine Silk Road. The archaeological value of the cultural relics at the South China Sea No.1 site is much greater than the economic value. At present, the excavation of the South China Sea No. 1 and the protection of the bronze relics housed at the Marine Silk Museum not only provide valuable historical information about wreck protection but also provide a strong reference for the study of marine water relics. It will provide reliable support forthe protection of our marine cultural resources. 2 �Analytical instruments The methods utilised to analyse the concretion on the bronze surface and the corrosion products included: an Olympus metallurgical microscope from Japan; the KSTAR Company’s HIROX KH-3000 3D video microscopy; Japan the Science RINT2000 X-ray diffractometer (copper target, slit DS = SS = 1 °, RS = 0.15mm, voltage 40kV, current 40mA); scanning electron microscopy and energy dispersive spectroscopy; Hitachi S3600N scanning electronic microscope (SEM) and the EDAX Genesis 2000XMS Xray energy dispersive spectroscopy (EDS) (SEM-EDS); and XPS. Results and analysis Fig.1a: copper coins from The South China Sea No.1.: (X. Tian). Coins surface morphology analysis Representative samples were taken from the concreted copper coins (Fig. 1a). 3D video microscopy was used to observe the surface morphology of the copper coins and the results are shown in Fig.1b.A metallographic microscope was used to observe the cross-section of the sample coins with the results shown in Fig.1c. Fig.1b demonstrates that the coin has an Fig.1b: The 3D video microscopic image of the concretion and corrosion on the surface of the copper coin.: (X. Tian). uneven distribution of black, brown and green coloured material on the surface. There are also varying degrees of spots, salt crystallization and a dark texture on the surface. 3 �Results of the metallographic microscopy (Fig.1c) identifies that the outside of the coins are corroded. The results also establish that a uniform phase is formed within the coins. This includes the yellow area interspersed with many black spots located inside the coin matrix, also seen in Fig.1c. The grey concretion can only be Fig.1c: The metallographic dark field image of the cross section of the copper coin.: (X. Tian). found on the edge of the thin layer and the corrosion products are located between the concretion and the metal matrix. Additionally, the coin is thin. Chemical composition of corrosion products The corrosion products on the coins from the South China Sea No. 1were analysed by XRD. The results are shown in Table 1. The major corrosion products include basic cupric chloride Fig.2a: SEM image of the metal matrix of the copper coin.: (X. Tian). [Cu2(OH)3Cl], cuprite (Cu2O), copper hydroxide [Cu (OH)2], cupric hydroxyl chloride[Cu(OH)Cl], and cuprous sulfate [Cu 2 (SO4)]. The composition and structure of the matrix of the coins The metal matrixes of the coins were analysed by SEM and EDS to investigate the composition and structure of the substrate shown in Fig.2. Fig.2a shows the SEM images of a sample coin’s metal matrix. Figs 2b, 2c, and 2d provide an example of Fig.2b: distribution image of Cu.: (X. Tian). the distribution of Cu, Pb and Snin the metal matrix, respectively. The SEM image of the copper coin metal matrix shows uneven grey spots, 4 �which are Pb-rich pockets distributed across the coin. Except for these Pb areas, Cu and Sn are evenly distributed throughout the matrix. EDS results show that the composition of the coins is as follows: Cu is about 94%, Pb is approximately 4%and Sn is only about 2%. Fig.2c:The distribution image of Pb.: (X. Tian). Analysis of the corrosion process While cutting the edge of the coins, only a little metal matrix was observed. The first step was to observe the outside of a cross-section of the coins through SEM and then analyse the elements of the different colour regions identified. The analysis results are shown in Fig.3 and Table 2. Fig.3 shows that Zone 1 is a black, loose surface layer along the outside of the coin. This is the concretion layer, which contains a small amount of Cu, but no Pb and Sn. Zone 2 is a white layer of uneven thickness, which contains S and Pb, and therefore may be PbSO4. Zone 3 is a greyish-black, banded structure, containing S, Pb, Cl and Cu, which may be PbSO4 and copper chlorides. Lastly, Zone 4 is Fig.2d: distribution image of Sn.: (X. Tian). grey and the largest area. This section contains Cu, Pb, Sn, Si and Cl, which corresponds closest to the coin metal matrix. Table 2 shows that the main elements in the corrosion products are Cl and S. After comparison of the results, Zone 2 contains the greatest amount of Pb, Zone 3 contains the greatest amount of Cu and Zone 4 contains the most Sn. Therefore, the Cu in the coin has preferentially corroded. 5 �In order to observe the change in the content of each element from the outer surface to the inner regions of the coin, SEM analysis was conducted. The results are shown in Fig.4. Fig.4 shows that the content of Cu, Sn and Ca change significantly in the white area, while the content of Si, Pb and Cl change only slightly. Pb is mainly found in Zone 2, while Sn occurs Fig.3: SEM image of the cross section of the outer layers of the copper coin.: (X. Tian). mainly in Zone4. Overall, the Cu content Cu changes in most zones and in the greyish black zone, Cu is greater, which maybe the residual Cu metal matrix. Discussions The corrosion layer found on thebronze artefacts from The South China Sea No.1 shipwreck was mainly turquoise in colour. The typical powdery rust coloured corrosion that falls Fig.4: The content line of different elements in the cross section of the copper coin.: (X. Tian). off when touched was uncommon on the copper coins. The corrosion products identified were Cu2(OH)3Cl, Cu2O, Cu(OH)2, Cu(OH)Cl, Cu(SO4)2. Copper chloride was one of the main corrosion products (e.g.Cu2(OH)3Cl and Cu(OH)Cl) identified. Chlorine easily induces bronze corrosion, so it is important to take the proper measures to remove as much chloride as possible, via proper desalination to effectively stabilise the metal. The analysis of the corrosion products provides data that will assist in deriving better methods for later desalination work. From the presence of copper chlorides (i.e. Cu(OH) Cl and Cu2(OH)3Cl) and cuprite (Cu2O) corrosion products, it can be deduced that the bronze in the South China Sea No.1 was primarily in anaerobic marine environment, which included Cl- and SO42- in solution. Where oxygen was more 6 �abundant loose concretion formed on the outside of the coins. There are, however, some instances when oxygen was sealed in the space between the original metal surface of the coins and the loose concretion. Thus, the oxygen depolarization controlled the electrochemical corrosion of the bronze. In this type of environment, Sn has a lower electrode potential than Cu, so it corrodes first, with the effect of Clspeeding up the rate of corrosion by combining with Cu and Sn ions to form new corrosion products. Conclusion. 1.The copper metal matrix contains mainly Cu, Sn and Pb at a ratio of 47:1:2, respectively. 2.The copper corrosion products mainly include: Cu2(OH)3Cl, Cu(OH) Cl, Cu2O, Cu(OH)2 and Cu(SO4)2。 3. Selective corrosion occurred between Cu and Sn in the bronze coin and the presence of Cl-increases the rate of corrosion in the electrochemical corrosion reaction. Table 1 sample NHTQ-1-a NHTQ-1-b NHTQ-1-c NHTQ-1-d NHTQ-2-b NHTQ-2-a Main composition Cu2（0H）3Cl、Cu2O Cu2（0H）3Cl、Cu2O Cu（0H）2 、Cu（0H）Cl、Cu2O Cu（0H）2、Cu（0H）Cl、Cu2O Cu（0H）2、Cu（0H）Cl、Cu2O、 Cu（SO4）2 Cu（0H）2、Cu（0H）Cl、Cu2O、 Cu（SO4）2 Table1:The XRD results from the analysis of the corrosion products from the copper coin from the South China Sea No. 1 shipwreck.: (X. Tian). 7 �Table 2 No. Elements（Wt%） Mg Al Si S Cl K Ca Fe Cu Pb Sn 1 3.0 17.4 36.8 7.7 1.8 3.9 2.6 21.7 5.1 — — 2 — — — 3.6 — — — — — 96.4 — 3 — — — 40.5 1.7 — — — 43.1 14.7 — 4 — — 1.8 — 0.7 — — — 5.7 23.1 67.7 Table 2:The elemental distribution of the cross section of the outer layers of the copper coin.: (X. Tian). Bibliography Beccaria, A. M., Mor, E. D., Bruno, G., Poggi, G.,1982. Corrosion of lead in sea water. British Corrosion Journal,Vol.17(2): 87-91. Gettens, R. J., 1964. The corrosion products of metal antiquities. Annual Report of the Board of Regents of the Smithsonian Institution, 1963, Vol. 1963: 547-568. Gettens, R. J., 1933. Mineralization, electrolytic treatment, and radiographic examination of copper and bronze objects from Nuzi. Zerox from Technical Studies 1: 118-142. MacLeod, I. D.,1991. Identification of corrosion products on non-ferrous metal artefacts recovered from shipwrecks. Studies in Conservation, Vol. 36(4): 222-234. MacLeod,I.D., 1985.The effects of concretion on the corrosion ofnon-ferrous metals. Corrosion Australasia, Vol. 10:10-13. MacLeod,I. D., 1982.Formation of marine concretions on copper and its alloys. International Journal of Nautical Archaeology, Vol. 11(4): 267-275. 8 �Nord, A. G., Lindahl, K., &Tronner, K., 1993. A note on spionkopite as a corrosion product on a marine copper find. Studies in Conservation, Vol. 38(2): 133-135. North,N.A.,1987.Conservation of Metals, In C. Pearson (Ed.),Conservation of Marine Archaeological Objects. Butterworths, Sydney:207-252 Scott, D. A.,2002. Copper and Bronze in Art: Corrosion, Colorants and Conservation. Getty Publications, USA. Biography. Xing-ling Tian is a conservation researcher who holds a doctor’s degree of Materials Science and Engineering from Beijing University of Chemical Technology. In 2003, Xing-ling Tian joined the Chinese Academy of Cultural Heritage (State Administration of Cultural Heritage Center of Underwater Cultural Heritage).In 2006, became a research associate. Past research interests have been predominantly concerned with the conservation of metal and wood, developing and applying research to new materials and techniques and currently I am focused on the conservation of underwater cultural heritage. 9 � Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Session 7: Preservation and Conservation of Wet Archaeological Materials and Site Management Subject The topic of the resource Interview with Session 7 chairs Vicki Richards and Jon Carpenter and links to the papers presented in the session. Description An account of the resource This session will focus on in-situ preservation and conservation management issues, conservation analyses and treatments, and applied conservation research of archaeological materials from freshwater, marine and wet terrestrial sites. The main purposes of this session are to encourage the exchange of ideas and practices as well as the development of conservation networks throughout the region. Presentations, posters and workshops are invited that address any of the following areas: • In situ preservation of marine archaeological materials, including reburial practices • Conservation management of shipwreck sites, including on-site monitoring • Conservation treatment case studies • Research into the analysis and treatment of wet archaeological materials • Review of the status of wet archaeological conservation programs in the Asia Pacific region • Development of collaborative conservation research and treatment programs Suggestions for additional topics are welcomed by the session organizers. Creator An entity primarily responsible for making the resource Vicki Richards and Jon Carpenter Document A resource containing textual data. Note that facsimiles or images of texts are still of the genre text. Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Study of the corrosion of copper coins from the wreck of 'The South China Sea No.' Description An account of the resource The South China Sea No.1 is the wreck of the longest, largest and most preserved shipwreck site in China. It is a classic example of bireme construction and navigational technology. The artefacts located on the site may provide many secrets of the Silk Road on the sea. Therefore, the archaeological value is greater than its economic value. In order to know more about the craftwork and the state of the coppers in this wreck, this paper will examine the concretion and corrosion on the surface of copper samples obtained from the upper layer of South China Sea No. 1. The samples were analysed with metallographic microscopy, 3D video microscopy, X-ray diffraction (XRD),X-ray fluorescence （ XRF) and scanning microscopy (SEM-EDS). The results show that the copper coin is tin-lead bronze, and the content of Cu is about 94%. The corrosion is mainly Cu2(OH)3Cl, Cu2O, Cu(OH)2, Cu(OH)Cl and Cu(SO4)2. The concretion on the surface of the copper coin is rich, but the matrix becomes thinner. Lead (Pb) is scattered freely in the matrix. Tin (Sn) is high in the corrosion layer, which shows that some Cu has corroded. The electrochemistry of the corrosion was controlled by oxygen depolarization. Selective corrosion occurred between Cu and Sn, and the effect of Cl- sped up the rate of corrosion in the electrochemical reaction. The results of the study can provide a reference for the protection of the copper artefacts excavated from South China Sea. Creator An entity primarily responsible for making the resource Xing-ling Tian Nai-sheng Li Zhi-guo Zhang, in Van Tilburg, H., Tripati, S., Walker Vadillo, V., Fahy, B., and Kimura, J. (eds.) Date A point or period of time associated with an event in the lifecycle of the resource 5/15/2014 Asia-Pac Session 7 2014 https://apconf-much.org/proceedings/files/original/3287c0c08fd1a9a23617a3b0cf880ef6.pdf acce7ed828087e393451ee686bcfe585 PDF Text Text The Australian Historic Shipwreck Preservation Project – interim progress report Debra Shefi, Peter Veth, Cassandra Philippou School of Social Sciences, Faculty of Arts, The University of Western Australia 35 Stirling Hwy, Crawley Western Australia 6009 E-mail: debra.shefi@uwa.edu.au Jennifer Rodrigues, Vicki Richards and Western Australian Museum, Shipwreck Galleries, 47 Cliff St, Fremantle, Western Australia 6160 Peter Harvey Maritime Heritage Unit, Heritage Victoria, Department of Transport, Planning, Local and Infrastructure 1 Spring Street, Melbourne, Victoria 3000 Australia Abstract In early 2012 the Australian Historic Shipwreck Preservation Project (AHSPP) was formally awarded a large Australian Research Council (ARC) Linkage Grant, enabling ten Partner Organisations to join with four Australian Universities in one of the largest multi-organisational maritime archaeology projects to be undertaken in Australia. The project involved a month-long excavation on the historic shipwreck Clarence (1850) in April/May 2012 and a complex reburial program in November 2012. Further in-situ preservation work is also being conducted on James Matthews (1841) in Western Australia to test experimental reburial approaches in an alternative marine environment. The work on Clarence is now in its research, analysis, monitoring and reporting phase, with artefact, sediment and chemical analyses being undertaken. This paper will provide an interim report on AHSPP since its launch at the 1 st Asia-Pacific Regional Conference on Underwater Cultural Heritage in Manila in 2011. It will provide analysis of some of the more significant artefacts and features revealed during excavation and approaches to long-term in-situ preservation and management of shipwreck sites. Key words: In-situ preservation, in-situ management, historic shipwreck, artefacts, site management 1 �Introduction In early 2012 AHSPP was formally awarded an ARC grant of $500,000 AUD to investigate the excavation, recording and in-situ reburial of wooden shipwrecks. The historic shipwreck Clarence (1850) in Victoria’s Port Phillip Bay was selected as the first case study to test the excavation and reburial methodology. The proposed research plan from the ARC application was presented at the 1st Asia-Pacific Regional Conference on Underwater Cultural Heritage held in Manila in November 2011 (Veth et al., 2011). The project commenced in February 2012 with the appointment of a project manager to organise fieldwork logistics alongside the commercial dive operators, Melbourne based company - Professional Diving Services, and the host organisation, Heritage Victoria. It was decided to commence diving operations in mid-April 2012 to take advantage of autumn tides and weather. In less than two months, a diverse multi-national team of 65 professional and volunteer archaeologists, divers, conservation scientists, photographers, artefact specialists and marine ecologists converged on Portarlington, Victoria to commence the survey, excavation, artefact cataloguing and in-situ reburial of Clarence. The excavation took place from a 12 m x 18 m jack up barge, which was towed by tugboat out to the site on the 12th of April, and placed alongside Clarence, off Edwards Point near the township of St Leonards. The barge was equipped with three shipping containers that held the artefact photography and x-ray systems, conservation and other general equipment and diving communication and safety equipment. Survey operations began on the 16th of April and continued for 29 days. During this time, diving, conservation and support teams were transported daily to the site using Heritage Victoria’s 8 m commercial Kevlacat Trim, with both underwater and topside support teams changing over throughout the day. Dive teams were tasked with placing sandbags along the exterior of the shipwrecked hull to provide structural support prior to reburial, completing a pre-disturbance marine ecology survey, obtaining sediment cores for baseline conservation data, excavating the 2 �starboard side of the wreck from the stern towards the bow (from 0 – 9 m along the baseline), recording the artefacts and exposed timbers in-situ, documenting all recovered artefacts ex-situ and reburying them on site (or in the nearby underwater repository), placing sacrificial wooden and metal samples on site and in the repository and backfilling the excavation trench. This was all achieved in 181 hours of diving over 17 diving days. Non-diving personnel were tasked with topside and off site duties including data input, purchasing, organisation of equipment and housekeeping. Clarence – Artefact and Site Features The artefacts recovered during the 2012 excavation included 109 individual artefact pieces, consisting of 102 database entries. All recorded artefacts were subsequently reburied; organic artefacts were placed in an underwater repository less than 10 m from the stern of the shipwreck, and ferrous and non-ferrous objects were reburied in the excavated trench. The range of materials found consisted of timber thought to be dunnage, a large number of cask components (staves and headpieces), concretions (including a concreted bolt), lead hull-sheathing, fragile pieces of leather, rope related to rigging, clear and olive-green glass pieces, a ceramic fragment, and an animal bone which appeared to be burnt. A leather bag or satchel was also identified in situ, however, this artefact was not raised. To date, analysis of the excavated artefacts continues and here a few selected items will be profiled. A more comprehensive report on the artefacts will be submitted later in 2014. Tierce casks The wooden cask components represented the majority of artefacts raised. The sizes of the staves and headpieces fit closest to the category of tierce casks. A tierce is an old measure of capacity equivalent to one third of a pipe, 42 wine gallons, half a puncheon or approximately 158 to 160 litres. The imperial tierce was 35 imperial gallons (~159 L)  the US tierce was 42 US gallons (~160 L). English stave lengths for tierce 3 Fig. 1: Branding mark on cask. (AHSPP). �casks were usually given at 31.5 inches (~800 mm) (Kilby, 1971: 52). The complete lengths for the Clarence staves averaged between 876 mm and 890 mm for the interior and 911 mm to 930 mm for the exterior. These measurements identify the excavated staves as slightly larger tierce casks than those traditionally described by the English. This variation in size could be because some tierce casks were made to store dry goods, in which case, they could be more rudimentarily manufactured as opposed to wet casks, which required a higher level of skill and precision for storing liquids and preventing leakages. The casks from Clarence have similar features found on casks from other shipwreck sites. These include branding marks, incised lines and circles (made by a scribe tool) for ease of reassembly (Fig. 1) and branded names (either complete or partial due to deterioration or breakage) on headpieces for identification purposes or indication of their contents. Hoop marks are also visible on the exterior of some staves where they are assumed to have been hammered in. Some limited evidence of concreted iron hoops has also been found. The branding names on the headpieces recovered from Clarence, however, suggest that either these casks contained ale or they are reused components. The average diameter of headpieces raised was 55 cm (21.7 inches), which closely coincides with tierce cask head diameters of 20.5 inches (52.1 cm) (Kilby, 1971: 52). The slight difference is understandable considering that the Clarence casks are Fig. 2: Headpiece inscribed with “J & R TENNENT”. slightly larger than the standard English (AHSPP). dimensions of tierce casks. The pitch (widest mid section) of the cask would be approximately 25¼ inches (64.1 cm) in diameter. The headpieces are attached to each other via wooden dowels along the joining flat edges or straight flush joints. Dowels and dowel holes were visible along the joining 4 �edges. The outer circumference is bevelled in order to fit into the bite or croze groove of the staves upon assembly of the cask. The tool marks and striations observed suggest that the staves and headpieces were machine made rather than handmade, which was more common in earlier centuries. In England, for example, the first patent for a coopering machine was taken out by Plasket and Brown in 1811 (Kilby, 1971: 65). At this time, however, most of these machines were crude and inefficient and were mainly used for cutting headpieces. Certainly by the 1870s, a number of cooperages were making tierces and cheap dry casks by machinery (Kilby, 1971: 65). Some sets of headpieces, consisting of the cant and middle pieces, are branded on the topside with the words, either partial or complete, “J & R TENNENT” (Fig. 2). To date, at least one identity of J. & R. TENNENT has been traced to Wellpark Brewery in Glasgow, Scotland, which was in operation in the 1840s. If some of the casks originated from an overseas brewery, it is possible that the casks and similar contents were continuing to be transported elsewhere or the casks or some components were being reused, as was Fig. 3: Headpieces inscribed with “SAMUEL” and “BURTON”. (AHSPP). common practice. Another name branded on other cask heads, again, either partial or complete, is “SAMUEL” and “BURTON” (Fig. 3). Preliminary research identifies a Brewer named 5 �Samuel Allsopp as well as The Burton Brewery Company, both based at Burton upon Trent in Staffordshire, England. Samuel Allsopp entered business in 1807 and during the 1840s, Allsopp’s brewery had an overwhelming superior reputation for their pale ale (Perkins, 2012). Contemporarily, the Burton Brewery Company, founded in 1842, was one of the largest brewers in Burton upon Trent in the nineteenth century and supplied ships in the early 1850s with ale. However, it still may have been too late to be contemporary with casks that were later transported via Clarence. Further research into the connection between the Clarence casks and the abovementioned brewing companies is warranted. Although a few leads for the branded names on the cask’s heads have been obtained, the possibility that some components or entire casks had been re-used has not yet been ruled out. Leather Bag or Satchel A leather bag or satchel was also found on the site partially buried under a semi-circular timber artefact. Based on discussions amongst divers who excavated the area and upon close examination of underwater images, this leather bag, left in situ (Fig. 4), is thought to be a bosun’s bag. The size and thickness of the satchel suggest it may have been used to carry tools (i.e. if one was repairing masts or rigging), as it could be slung over the shoulder via a strap on the side. Interestingly, an image in Kilby (1971: 164) on coopers and their craft shows a nineteenthcentury travelling cooper carrying a Fig. 4: Leather bag or satchel left in-situ. (AHSPP). possible leather bag or basket over the shoulder containing tools. 6 �Clarence – Management Monitoring and Management In June 2012, shortly after the completion of the April/May Clarence excavation, a small team of researchers and volunteers returned to the site to finish backfilling the trench and artefact reburial depot to a minimum of 50 cm sediment coverage, as outlined in the research methodology. Final fieldwork took place in November when the site was covered with shade cloth and PVC tarpaulins to encourage anaerobic conditions and protect the site from anthropogenic and natural impacts (Fig. 5). Sediment core samples were collected for physico-chemical analysis and a marine biological survey was completed. In both March and September 2013, visual inspections were conducted and the site appears to have stabilised. A small team returned to the site in November 2013 to extract sediment core samples and sacrificial wood and metal samples. Management of the site has not ceased with the reburial of Clarence. monitoring, Long-term including Fig. 5: PVC tarpaulins on Clarence (J. Carpenter). visual site inspections and a program of regular compliance patrols, has been established. These site visits are conducted during periods of calm weather and on weekends and public holidays, when recreational boating activities peak. Individuals found within the 100 m protected zone surrounding the site are issued with either official warnings or infringement notices. Regular patrols by Heritage Victoria at Clarence have resulted in a 7 �high level of compliance by recreational anglers, with boats clustering around the boundaries of the site but complying with the exclusion zone itself. Although increased enforcement activities seem the likely driver for the improvement in compliance, consideration should also be given to the fact that stabilisation works on the site have substantially altered the seabed terrain and associated biology. Biological surveys indicate the variation in species on-site has not been greatly impacted, but this could have reduced the numbers of desirable fish catch, possibly also helping to explain the decreased fishing activity over the site. Digital Outreach In addition to on-site visitation and management of Clarence, AHSPP has focused on disseminating information beyond the academic and scientific communities to the wider public. This includes providing Project Updates for meetings of the Commonwealth Historic Shipwreck Act delegates, the AIMA quarterly newsletter and the AHSPP website (www.ahspp.org.au). Public lectures and professional papers have also been presented nationally and internationally with a major paper on the project published in the 2013 AIMA Bulletin (Veth et al., 2013). Moreover, in lieu of tangible displays, upon AHSPP digital dissemination relies media for Fig. 6: Shade cloth cover over the top of the cofferdam surrounding of James Matthews (J. Carpenter). information. This includes the project website and two public-focussed outreach projects. The first project is a triptych display banner that tells the story of the AHSPP Clarence case study using 8 �simple text and images. The pop-up banners are easily transportable and throughout 2013 and 2014 will be used as a travelling exhibition to Partner Organisations and collaborating institutions around Australia. They are also available for further use at presentations and conferences. The second outreach project was a curated digital database entitled ‘Preserving the Colonial Trader Clarence (1850)’ (the Clarence Anthology), which is publically accessible through library database subscriptions to BiblioBoard. This contains both web-based access and applications for mobile devices and Apple iPad and android tablets (http://www.biblioboard.com/libraries.html). The Clarence Anthology was the first Australian project created for BiblioBoard and also the company’s first archaeological and shipwreck database. The concept was to curate a collection of images, documents and multi-media items (including video and audio via web streaming) into an ‘anthology’ as part of BiblioBoard’s new ‘Artifact of History’ module. The module is made up of a wide range of historical sources that are focused on historical artefacts and archaeological discoveries. The Clarence Anthology consists of more than 270 files, primarily underwater site and artefact photographs, topside images and underwater and topside video. It also includes presentations, previous site research, historical research, media interviews and an edited oral history interview with a descendant of the captain of Clarence. This digital resource thus allows for enriched, well-curated content to be accessible to a broader, technologically-progressive audience and also facilitates access to associated grey literature. The Clarence Anthology is currently being utilised as a test case for future online curation of archaeological projects. As such, this method of community outreach may be recognized as an appropriate platform for future presentation of archaeological sites, in particular in-situ preservation projects where artefacts are returned to the seabed with no plan for future conservation and long-term museum curation. James Matthews 9 �Since the inception of AHSPP it was duly noted that to be a truly national research project, other sites around Australia should be included in the longitudinal in-situ preservation study for comparative analysis. Following the reburial success of Clarence in November 2012, and due to prudent project management, it became clear that the AHSPP could expand to a second case study. Partner Investigator Vicki Richards and colleagues at the Western Australian Museum (WAM) subsequently recommended the reburial of James Matthews (1841) in Cockburn Sound, Western Australia using a preferred cofferdam solution. Under the aegis of the AHSPP, WAM began organising this innovative reburial project in April 2013. Background James Matthews, originally known as Voltigeur, was a French-built wooden brig (approximately 24 m length x 6 m breadth x 3 m depth). In 1836 the vessel was sold to a Brazilian slave dealer and registered as Don Francisco under the Portuguese flag. For the following year, the vessel operated in the illegal slave trade between Africa and the West Indies until its capture by the British in 1837. Contemporarily, in 1836, British Parliament passed a Bill establishing an end to slavery. At this time, ships were seized and destroyed, often resulting in the vessel being dismantled and sold for scrap or burnt to the waterline and sunk (Henderson, 1977). This was obviously not the case with Don Francisco, which was sold and re-registered as the trading vessel James Matthews (Henderson, 1980). In July 1841 the ship sailed for the Swan River colony in Fremantle, Western Australia, but shortly after its arrival a violent storm struck the port and the vessel sank. Local divers came across the site in 1973, 12 km south of Fremantle, approximately 100 m off shore in 2-3 m of water (Henderson, 1977). Four seasons of excavation were carried out by WAM between 1974 and 1977. All loose artefacts were recovered and stabilised by standard conservation treatments appropriate for each material type and the excavation trenches were backfilled with the original overburden. The site remained buried for many years and was still relatively stable in the 1990s. However, in early 2000 it was observed that the edges of the 10 �wooden vessel and timbers at the stern and bow were exposed and severely degraded by marine borers and the extent of exposure was increasing every year. Therefore, devising an appropriate in-situ management plan to mitigate continuing deterioration was of paramount importance. Experimental Remediation Strategies and Monitoring Over the next ten years, a number of surveys and experiments were expedited to assess the most significant physical, chemical and biological deterioration processes impacting the site and determine an appropriate long-term in-situ preservation strategy to stabilise James Matthews. This included trialling different in-situ preservation strategies on-site, for example: sand bags; sediment trapping experiments using artificial seagrass, shade cloth mats and a cofferdam consisting of four environmentallyinert, interlocking medium density polyethylene ‘crash barrier’ units filled with surrounding sediment. More importantly, a long-term monitoring programme was also introduced that consisted of measuring sediment and seabed response and any changes in the sediment micro-environment via microbiological and physico-chemical analyses. Based on these results, the crash barrier cofferdam technique appeared to be the best solution for the in-situ preservation of James Matthews (Richards et al., 2009; Richards, 2012). However, due to the significant cost of this mitigation strategy (~$25,000 AUD for 40 crash barriers, geotextile and polymeric sandbags) and the local economic environment, the cofferdam solution could not be funded through WAM’s budget. Therefore, in 2010, the more exposed sections of the site were covered with shade cloth, which was economically more viable but resulted in undesirable toe scouring around the edges of the mats. The site continued to be monitored at regular intervals over the next two years (Richards, 2012). The AHSPP and the Cofferdam Solution Preparations for the reburial of James Matthews commenced in April 2013, with fieldwork occurring from 18-22 November 2013. A total of 22 people, including the AHSPP Chief Investigator and Acting Project Manager, WAM staff from the Materials 11 �Conservation and Maritime Archaeology Departments, practitioners from other Partner Organisations and volunteers, were involved during an intensive five-day fieldwork period. During this time, 36 road crash barriers were deployed on-site in a semi-elliptical arrangement, anchored in place with a minimum of 120 kg of blue metal per barrier and 20 m3 of clean, washed proprietary sand dumped within the confines of the cofferdam via a manufactured sand barge, which provided a sterile sand layer of approximately 515 cm over the entire site. A more comprehensive account of the fieldwork logistics and deployment procedures are outlined in Richards et al. (2014) published in this volume. The amount of sand required to fill the cofferdam to an optimum level of 0.8 m is approximately 165 m3, which was impossible to achieve in the five-day fieldwork interval. With a considerable reduction in personnel after the fieldwork had concluded, it was decided to cover the top of the cofferdam with 70% UV stabilised shade cloth (Fig. 6). The suspended shade cloth aims to a) preclude the ingress of dead seagrass and other organic material and b) encourage deposition of fine sand particles suspended in the water column, through the shade cloth and onto the site. In early 2014, the cofferdam will continue to be filled to the required depth (0.8 m) by dredging local surrounding sediment onto the site ensuring that minimal organic matter is incorporated within the backfilled sediment. On-site monitoring of sediment characteristics and analysis of sacrificial samples will then proceed, replicating the monitoring strategy used on the Clarence site. This should allow for meaningful comparative analyses of these reburial interventions in different contexts. The efficacy of different reburial and stabilisation techniques can thus be systematically tested providing an evaluation of optimal protocols for the in-situ preservation and management of historic shipwrecks determined to be ‘at risk’ in both Australian and other waters. Conclusion The primary aim of the Australian Historic Shipwreck Preservation Project is the development of an optimal in-situ preservation protocol for historic shipwrecks at risk. Longitudinal recording, reburial and ongoing monitoring at both Clarence and James 12 �Matthews, occurring in different geomorphic and energetic contexts, will provide an invaluable comparative study towards this end, and will continue throughout 2014. As outlined in this paper, data collection, analysis and interpretation are continuing. The results from the archaeological, conservation, sedimentary and biological studies will be published in a major excavation and fieldwork report due for completion in 2015. Analyses of the artefacts, geochemistry of the sediments, pre- and post-disturbance biological surveys, and condition of the sacrificial tabs, will also be published over the next several years. Bibliography Henderson, G., 1977. Four seasons of excavation on the James Matthews wreck. The First Southern Hemisphere Conference on Maritime Archaeology, Perth, Western Australia. Henderson G., 1980. Unfinished Voyages. Western Australian Shipwrecks 1622-1850. University of Western Australia Press, Nedlands. Kilby, K., 1971. The Cooper and His Trade. Linden Publishing, Fresno. Perkins, B., 2012. Tennent’s India Pale Ale. Retrieval December 20, 2013. From http://barclayperkins.blogspot.com.au/2012/02/tennents-india-pale-ale.html Richards, V., 2012. In-situ preservation and monitoring of the James Matthews shipwreck site. Conservation and Management of Archaeological Sites, Vol. 14 (1-4): 169-181. Richards, V., Godfrey, I., Blanchette, R., Held, B., Gregory, D. and Reed, E., 2009. Insitu monitoring and stabilisation of the James Matthews site. In K. Straetkvern and D.J. Huisman (Eds.), Proceedings of the 10th ICOM Group on Wet Organic Archaeological Materials Conference, Amsterdam, 10-15 September 2007, Rijksdienst voor Archeologie, Cultuurlandschap en Monumenten (RACM), Amersfoot: 113-60. Richards, V., MacLeod, I. and Veth, P., 2014. The Australian Historic Shipwreck Preservation Project – In-situ preservation and long-term monitoring of the Clarence (1850) and James Matthews (1841) shipwreck sites. In S. Tripati and V. Walker (Eds.), 13 �Proceedings of the 2nd Asia-Pacific Regional Conference on Underwater Cultural Heritage, 12-16 May 2014, Honolulu, Hawaii, Hawaii. Veth, P., Philippopu, C., Richards, V., Staniforth, M., Rodrigues, J., Khan, A., Creagh, D., Viduka, A., Barham, A., and MacLeod, I., 2013. The Australian Historic Shipwreck Preservation Project 2012: First Report on the background, reburial and in situ preservation at the Clarence (1841-50). Bulletin of the Australasian Institute for Maritime Archaeology, Vol. 37: 1-19. Veth, P., Viduka, A., Staniforth, M., MacLeod, I., Richards, V. and Barham, A., 2011. The Australian historic shipwreck protection project. In M. Staniforth, J. Craig, S.C. Jago-on, B. Orillaneda and L. Lacsina (Eds.), Proceedings of the Asia-Pacific Regional Conference on Underwater Cultural Heritage, 8-12 November 2011, Manila, Philippines, Jericopim Publishing House, Manila: 753-762. Biography Debra Shefi is a Research Assistant Professor in the Department of Archaeology at the University of Western Australia and is the Acting Project Manager for the Australian Historic Shipwreck Preservation Project (AHSPP). She joined AHSPP after obtaining her PhD from Flinders University, where her thesis investigated the relationship between the in-situ preservation of underwater cultural heritage in law and practice. 14 � Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Session 7: Preservation and Conservation of Wet Archaeological Materials and Site Management Subject The topic of the resource Interview with Session 7 chairs Vicki Richards and Jon Carpenter and links to the papers presented in the session. Description An account of the resource This session will focus on in-situ preservation and conservation management issues, conservation analyses and treatments, and applied conservation research of archaeological materials from freshwater, marine and wet terrestrial sites. The main purposes of this session are to encourage the exchange of ideas and practices as well as the development of conservation networks throughout the region. Presentations, posters and workshops are invited that address any of the following areas: • In situ preservation of marine archaeological materials, including reburial practices • Conservation management of shipwreck sites, including on-site monitoring • Conservation treatment case studies • Research into the analysis and treatment of wet archaeological materials • Review of the status of wet archaeological conservation programs in the Asia Pacific region • Development of collaborative conservation research and treatment programs Suggestions for additional topics are welcomed by the session organizers. Creator An entity primarily responsible for making the resource Vicki Richards and Jon Carpenter Document A resource containing textual data. Note that facsimiles or images of texts are still of the genre text. Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource The Australian Historic Shipwreck Preservation Project: interim progress report Description An account of the resource In early 2012 the Australian Historic Shipwreck Preservation Project (AHSPP) was formally awarded a large Australian Research Council (ARC) Linkage Grant, enabling ten Partner Organisations to join with four Australian Universities in one of the largest multi-organisational maritime archaeology projects to be undertaken in Australia. The project involved a month-long excavation on the historic shipwreck Clarence (1850) in April/May 2012 and a complex reburial program in November 2012. Further in-situ preservation work is also being conducted on James Matthews (1841) in Western Australia to test experimental reburial approaches in an alternative marine environment. The work on Clarence is now in its research, analysis, monitoring and reporting phase, with artefact, sediment and chemical analyses being undertaken. This paper will provide an interim report on AHSPP since its launch at the 1st Asia-Pacific Regional Conference on Underwater Cultural Heritage in Manila in 2011. It will provide analysis of some of the more significant artefacts and features revealed during excavation and approaches to long-term in-situ preservation and management of shipwreck sites. Creator An entity primarily responsible for making the resource Debra Shefi Peter Veth Cassandra Philippou Jennifer Rodrigues Vicki Richards Peter Harvey, in Van Tilburg, H., Tripati, S., Walker Vadillo, V., Fahy, B., and Kimura, J. (eds.) Date A point or period of time associated with an event in the lifecycle of the resource 5/15/2014 Asia-Pac Session 7 2014 https://apconf-much.org/proceedings/files/original/c448dc07fc1e004f3e778774444ae52b.pdf 5a5baab2f4bff3476b0dbbb9ff0f13ec PDF Text Text The Australian Historic Shipwreck Preservation Project: In-situ preservation and long-term monitoring of the Clarence (1850) and James Matthews (1841)shipwreck sites Vicki Richards Department of Materials Conservation, Western Australian Museum Shipwreck Galleries, 45-47 Cliff St Fremantle, WA 6160 Australia Email: vicki.richards@museum.wa.gov.au Ian MacLeod Western Australian Maritime Museum, Peter Hughes Drive, Victoria Quay, Fremantle, WA 6160 Australia Peter Veth School of Social Sciences, Faculty of Arts, The University of Western Australia, 35 Stirling Hwy Crawley, WA 6009 Australia 1 �Abstract Increasingly archaeologists are opting for on-site examination, reinterment and in-situ preservation of underwater cultural heritage sites as the first option in the management of sites at risk as opposed to the more traditional excavation, recovery, conservation and display/storage methods. This decision will inevitably be based on significance assessment, degree of perceived risk and resourcing issues. However, long-term monitoring must become an integral part of these management programmes in order to quantitatively evaluate the effectiveness of the in-situ preservation techniques employed. Absence of monitoring is equivalent to abrogation of responsible management and in some cases can be considered tantamount to cultural vandalism. In 2012 the Australian Historic Shipwreck Preservation Project (AHSPP) commenced, having secured funding through a substantial Australian Research Council Linkage Grant with 10 Australian Partner Organisations and three universities. One of the major aims of the project is to develop a protocol for the excavation, detailed recording and reburial of significant shipwrecks under threat, fostering a strategic national approach for the management of underwater cultural heritage sites at risk. Two historically significant shipwreck sites were chosen for this longitudinal comparative study – the Clarence (1850) located in Port Phillip Bay, Victoria and the James Matthews (1841) which lies in Cockburn Sound, Western Australia. Both sites have been preserved in situ using two very different but innovative remediation strategies. More importantly a long-term monitoring programme has been implemented which will characterise changes in the reburial environment and the effect on the reinterred materials. In this way, the efficacy of both in-situ preservation techniques will be systematically tested, providing a comparative analysis of practical protocols for the long-term protection and management of underwater archaeological resources. Key words: In-situ preservation, Underwater cultural heritage, Shipwrecks, monitoring, Conservation management Introduction The AHSPP is a national collaborative project funded by an ARC Linkage Grant which commenced in February 2012. With ten state, territory and federal Partner Organisations and three collaborating universities, this is the largest multi-government, 2 �multi-institutional maritime archaeological project ever initiated in Australia. The idea of a national collaborative research project arose from the 2008 review of the Australian Commonwealth Historic Shipwrecks Program (HSP). The report suggested that the HSP had not developed a maritime specific conservation management planning process for underwater cultural heritage (UCH) sites including nationally standardised processes and procedures, capacity for the excavation of UCH sites that are considered under threat and general guidelines for site management and in-situ preservation of UCH material. The ASHPP aims to address some of these issues by investigating and preserving in situ, in accordance with the UNESCO Convention on the Protection of the Underwater Cultural Heritage, the Clarence (1850) shipwreck located in Port Phillip Bay, Victoria and the James Matthews (1841) which lies in Cockburn Sound, Western Australia. The Clarence was considered an ideal site for this project for a number of reasons. This early colonial Australian built vessel was test excavated and surveyed in the 1980s (Harvey, 1989), providing a baseline for ongoing longitudinal comparative research. The site is relatively small (16.5m length; 6.2m width) and easily accessible as it lies in 5m of water at a location close to the major population centre of Melbourne. The site is subject to continuing anchor damage by illegal recreational anglers as well as the natural impact of the strong currents experienced in Port Phillip Bay and is considered under serious threat. The ex-slaver turned colonial trading vessel, James Matthews was chosen as the second site. It is also relatively small (24m length; 6m width) and located 12km south of Fremantle, lying approximately 100m off shore in 23m of water. More importantly, it has been the subject of a long-term detailed in situ conservation management research programme with more than 10 years of accumulated data on the efficacy of three different experimental reburial strategies trialled on-site (Richards et al., 2009).The synergistic impact of industrial activity and natural near-shore sedimentary processes has resulted in continued exposure and rapid deterioration of the site. The implementation of appropriate long-term in-situ preservation strategies for both sites, supported by an extensive monitoring programme to assess the viability of the different methodologies, was of paramount importance. However, in order for any in-situ preservation strategy to be successful the following points must be addressed in the overall management plan: 3 �1. Ascertain the extent of the site. 2. Assess the most significant physical, chemical and biological deterioration processes occurring on the site. 3. Assess the pre-disturbed local burial environment and the major factors affecting the long-term stability of the site. 4. Identify the major material types present on the site and their extents of deterioration. 5. Implement an appropriate in-situ preservation strategy or combinations thereof, to mitigate continued deterioration and stabilize the site long-term. 6. Implement a long-term monitoring programme to evaluate the efficacy of the implemented in-situ preservation strategy. 7. Provide alternative plans and procedures if the implemented in-situ preservation strategies are unsuccessful. 8. Conservation, storage and curation of any recovered artefacts. Each of these points is integral to a process-based approach when assessing underwater cultural heritage sites and establishing successful long-term conservation management plans (Richards, 2011). All eight points were addressed through application of previous research results and during the development of comprehensive research designs that included extensive methodology components and monitoring programmes for each site prior to the implementation of any reburial strategies. Clarence - Excavation, Conservation and In-situ Preservation The first fieldwork period on the Clarence occurred from 16 April to 15 May 2012. All activities were conducted from a 18m x 12m jack-up barge, set 3.5m above sea level, located directly adjacent to the site. The deposition of 1700 UV stabilised polypropylene woven sand bags onto the site was Fig. 1 Biological growth on the Clarence site in November 2013. (J. Carpenter) 4 �executed from support vessels. Adverse weather limited the excavation to only 9m of the starboard side, which was fully recorded. Only 35 artefact assemblages were recovered and kept wet at all times with seawater as opposed to fresh water to avoid osmotic shock when reburied. After full documentation the artefacts were prepared for reburial by wrapping them in polyester geotextile (Bidim A14), followed by a high density polyethylene shade cloth protective wrapping (Coolaroo Exterior Fabrics - Extra Heavy (84-90% UV Block) secured by cable ties. The artefacts were then placed in wet storage until the reburial phase of the project commenced. Previous research has established the 50cm datum as the minimum depth of burial for the protection of recovered artefacts (Nyström-Godfrey et al., 2011). It was decided that the few, smaller metal, glass and ceramic artefacts could be reinterred on the wreck site as it would be possible to obtain greater than 50cm of sediment coverage. However, because they were different material types they had to be separated by at least 50cm in order to minimise the chances of unwanted chemical interactions. Owing to the larger size of the packed organic artefacts, it was not possible to rebury them on-site, therefore they were reburied in an off-site storage depot in order to obtain the minimum depth of burial. A proprietary 2000L high density polyethylene water tank was purchased, the ends cut off and the tank sawn in half. This cylinder (1.0m height; 1.2m diameter) was then dredged into the seabed about 10m south of the stern. The sand was dredged from within the confines of the cylinder and the least degraded organic artefacts placed at the bottom of the depot, covered with 10cm of surrounding sand then the more fragile organics were placed on top of this layer. The depot was then backfilled with surrounding sediment, covered with shade cloth and anchored with polypropylene sand bags. Towards the end of the fieldwork period, the excavated area including the reinterred artefacts was backfilled with dredged sediment from the site, however due to the fine nature of the clay deposit some was lost from the sediment traps and therefore the forward section of the excavation trench was backfilled with proprietary sand emptied from the sand bags on the site. Unfortunately, the weather deteriorated so it was not possible to adequately rebury the entire excavation trench and the off-site reburial depot 5 �to the minimum 50cm datum. These areas were stabilised with a layer of shade cloth and additional sand bags as an interim remediation measure. Three weeks later saw the reburial of the excavation area and the depot with further proprietary sand so that an average reburial depth of 1m was achieved. This was considerably deeper than the pre-disturbance sediment profile. The backfilled areas were then stabilised with a layer of shade cloth, anchored with more sand bags until the final phase of the remediation strategy could be completed later in the year. In November 2012 the final phase of the in situ preservation strategy commenced. This entailed filling and depositing a further 1800 sand bags on the site, removing the sand bags and shade cloth deployed in June, repositioning and adding more sand bags to adequately support some of the higher profile structural features on the port and starboard side of the wreck, covering the site with a shade cloth mat and finally protecting the site with polyvinyl chloride (PVC) tarpaulins. A pre-prepared 250m2 shade cloth mat (3 x 25m long x 3.66m wide sections joined together by cable ties) was deployed flush over the entire site conforming to the undulations of the wreck profile. The shade cloth was folded in a concertina fashion, which allowed the entire mat to be fanned out, starting down current, without recourse to deploying it in separate sections. The mat was then anchored with approximately 250 sand bags. The shade cloth mat will encourage the formation of an anaerobic environment in a relatively short period of time. However, because the shade cloth could be severely damaged by anchors it was covered with three 7m x 14m x 2mm PVC tarpaulins for further protection. The tarpaulins could not have been placed directly onto the site without the underlying shade cloth mat because a) the PVC was just negatively buoyant and relatively inelastic so the tarpaulins could not conform closely to the site profile leaving large water spaces around the higher profile structures, which would take too long to become anaerobic and b) the polyethylene mesh allowed the tarpaulins to slip and be easily moved into the correct position so they could be joined together with minimal gaps. Most importantly, 6 �the tarpaulins will minimise the continuing physical damage to the wreck site and should further encourage anaerobic conditions on-site. Each tarpaulin was deployed individually, with each end unrolled from the mid-section of the site. When all three tarpaulins were in the correct position they were joined together with cable ties through pre-prepared plastic eyelets and heavy duty nylon tabs. Sand bags were then tied in place along the seams and edges of the mats with previously installed nylon straps. Another layer of sand bags was then placed on top of these to minimise any gaps along the seams. Approximately 3-6 lines of sand bags were then placed along the bow and stern edges of the tarpaulin and another line of bags along the port and starboard side edges to seal any gaps and minimise water movement under the tarpaulin by strong currents and potential lifting by anchors. Finally, the entire interior of the tarpaulin was covered with approximately 1300 sand bags for added protection. The same procedure was followed for deploying the shade cloth and PVC tarpaulin (2m2) over the off-site reburial depot. Subsequent visits in March, September and November 2013, indicated that the in situ preservation strategy had been successful to date. All sand bags were still in place, there was extensive biological growth on the site and considerably more sediment buildup around the sand bags on top of the tarpaulins (Fig. 1). In addition, the sediment under the shade cloth was grey/black in colour indicating a low oxygen environment. The inspections showed that two of the higher profile ribs had broken through the protection and these will be wrapped in geotextile followed by impermeable black plastic. Any additional breakouts will be managed in the same fashion. Obviously, regular monitoring of any in-situ reburial strategy is essential in order to ensure continued longterm protection of the site. James Matthews – In-situ Preservation A comprehensive pre-disturbance survey and research into broader scale coastal processes and localised sediment level monitoring began in 2000. This work was extended in 2002 to assess the efficacy of sand bags, sediment trapping experiments 7 �using artificial seagrass and shade cloth mats and a cofferdam consisting of four environmentally inert, interlocking, medium density polyethylene ‘road crash barrier’ units (2m length; 0.9m height) filled with surrounding sediment, as site management methodologies. Long-term monitoring of the sediment to changes in micro-environment via microbiological and physico-chemical analyses were initiated (Richards et al., 2009).The crash barrier cofferdam technique appeared to be the best solution. Preparations for this large-scale reburial commenced in April 2013 with a total of 22 personnel(AHSPP Chief Investigator and Acting Project Manager, Western Australian Museum staff, practitioners from Partner Organisations and volunteers) involved duringthe intensive five day fieldwork period from 18-22 November 2013.Personnel were divided into 2 to 4 smaller teams dependent on the activities of the day. The two main teams consisted of a land-based team, which filled 1400 x 20kg sand bags with clean, washed proprietary sand (20m3 or 28 tonne) and the boat-based team, consisting of divers, boat handlers and support crew carried out all sea-based work on the wreck site. In addition two smaller teams were organised during the course of the fieldwork;a sand-barge team, which assembled and dismantled the sand barge and a shore-based team, which transported sand bags from the Museum to a beach about 100m from the wreck site and loaded the barge. Prior to the main program all previous site stabilisation equipment of anodes, sand bags and shade cloth were removed and a rope guideline was placed around the periphery of Fig. 2 Snorkelers sinking a RCB on the James Matthews site. (P. Baker) the site, which assisted in the 3 day deployment of the road crash barriers (RCBs), about 0.5-1.0m away from the wreck site in a semi-elliptical arrangement. Each RCB unit and connecting pin (0.9m length; 0.09m diameter) was filled with 20 kg and 5kg of blue metal (14mm), respectively on board a rented dive boat. The floating RCB and pin were then transported upright to the appropriate position on the wreck site using a small tender, then three snorkelers slowly sank the barrier via air displacement (Fig. 2). Two 8 �divers received the sinking RCB and the connecting pin and physically manoeuvred the barrier into the correct position, inside the guideline and then locked it in position with the pin. The RCBs weighed approximately 15kg under water and were easily manoeuvred on the seabed. Following this procedure 36 RCBs were individually deployed on-site before they were permanently anchored in place with a minimum of 120kg of blue metal per barrier. The initial sealing of the gaps in the Fig. 3 Plastic damp coursing anchored over the gaps between the RCBs with zinc tek screws. (J. Carpenter) coffer dam with 2m long; 1m wide black plastic strips proved to be ineffective due to wave action across the site so they were replaced with high density, plastic roof damp coursing (450mm width; 500µm thick) about 1.5-2.0m in length, placed over the gaps and anchored flush against the inner surfaces of the RCBs with zinc alloy tek screws (Fig. 3). Operation of the sand barge, designed to bring clean, washed sand to the enclosed wreck inside the RCB ring, proved that a beach based operation was not efficient since it involved multiple handling steps and took one day to deliver 3.5 tonnes of sand. The best method involved directly loading the barge from the rented dive boat moored adjacent to the site to minimise the distance the sand barge would need to be towed (Fig. 4).Twenty tonnes (1015 x 20kg bags) of sand was delivered to the site over the last two days of the fieldwork leaving8 tonne of sand at the Museum. The second phase of fieldwork was conducted over four days in early to mid-December 2013. By direct loading from the museum truck alongside the sand barge at the nearby Jervoise Bay Yacht Club, then towing the device to the wreck site a total of 8 tonne of sand was dumped on-site in one day with only 9 personnel. Dead seagrass that had begun to accumulate within the confines of the cofferdam was placed in bags and removed from the site. 9 �A total of 165m3 or 230 tonne of sand is required to achieve the desired 0.8m sediment height within the confines of the cofferdam. The enormity of this task became apparent after dumping28 tonne of sand which only produced a 5-15cm sterile sand layer. By deploying 4m wide strips of Fig. 4 Dumping of sand from the sand barge on the James Matthews site. (J. Carpenter) Armashade70% UV block shade cloth top over the top of the coffer dam it was hoped that the natural entrapment of fine sand particles suspended in the water column will assist in filling the cofferdam and also prevent ingress of dead seagrass. Seven panels with a 30cm overlap were sewn together with cable ties, which also enabled attachment to the RCBs (Fig. 5). In early 2014, the cofferdam will be filled to the required depth by dredging local surrounding sediment onto the site ensuring that minimal organic matter is incorporated within the backfilled sediment. Conservation Monitoring Programme Pre-disturbance Surveys The environmental characteristics of the pre-disturbed local burial environment should be assessed prior to reburial in order to assist in determining the inherent stability of the site and the major degradation mechanisms occurring on-site. In addition, this predisturbance information will be used as baseline data to assist in determining if and when the reburial environment returns to its original pre-burial state and the rate at which this occurs following the changes that necessarily accompany reburial. Analyses on both the Clarence and James Matthews sites included the chemistry of the seawater, pore water and sediments [pH; redox potential (Eredox); salinity, dissolved oxygen levels, total iron and organic content; sulphide and sulphate concentrations; nutrient (nitrogen and phosphorus)levels], the type and nature of the sediments (loss on ignition; particle size distribution; porosity) and the level and type of microbiological activity within the sediment. A 3,000km separation between the Clarence site and specialist microbiological assays in WA precluded microbiological analyses of those sediments. 10 �It is also important to obtain an understanding of the extent of deterioration of the major material types present on a site prior to reburial. Moreover, it is essential to collect this baseline data for long-term comparative analysis to quantify the effect the mitigation strategy is having on the reburied materials. A full pre-disturbance corrosion survey [pH, corrosion potential Fig. 5 The RCB cofferdam prior to the last length of shade cloth being deployed.(J. Carpenter) (Ecorr), total depth of concretion and corrosion (dtotal), the total depth of corrosion (dc)] was performed on the James Matthews site but no such survey was conducted on Clarence due to the lack of exposed metal objects. In addition, in situ pH profiles and pilodyn measurements were taken on exposed structural timbers on the James Matthews site, however only pilodyn data was collected from timbers on the Clarence site. Wood samples were collected from both sites for wood identification, maximum water content (Umax), microscopic and Fourier transform infra-red spectrometric (FTIR) analysis. Post Reburial Surveys The biological and physico-chemical environment of the reburial mound should be monitored at regular intervals. Hence, the same suite of analyses will be performed on sediments recovered annually from the Clarence and James Matthews sites post reburial as was previously described for the pre-disturbed environment. However, since destructive sampling of reburied archaeological materials is inherently invasive, sacrificial modern samples, such as wood blocks and metal coupons, were included in the reburial mounds (Fig. 6). 11 �Fig. 6 The sacrificial wood and iron samples on the Clarence site prior to reburial.(J. Parkinson) Sacrificial wood samples and modern ferrous alloys were reburied on both wreck sites. There were significant amounts of copper alloys (e.g. fastenings, sheathing, etc) present on the James Matthews site, therefore duplicate copper alloy coupons were also reburied on-site. One of the duplicate wood, iron and copper sacrificial samples were wrapped in Bidim A14 geo textile to ascertain its protective effect on reburied artefacts. Each set of samples had to be reburied at least 1m apart to ensure there would be no influence of the metal corrosion products on the degradation of the wood samples and to minimize proximity corrosion. The sacrificial samples will be recovered and analysed annually. The same suite of insitu and ex-situ analyses will be performed on the samples post reburial as was previously described in the pre-disturbance surveys. However, additional analyses [i.e. weight loss, scanning electron microscope/energy dispersive x-ray analysis (SEM/EDAX) and x-ray diffraction spectroscopy (XRD)] will be performed on the metal coupons. The results of the biological and physico-chemical analyses of the sediments can then be correlated to the extents of deterioration of the sacrificial samples and extrapolated to the condition of the reburied archaeological material. Conclusions One of the major aims of the AHSPP is to develop a protocol for the excavation, detailed recording and reburial of historic shipwrecks under threat by anthropogenic or natural forces. On-site monitoring of the sediment and analysis of sacrificial samples on the Clarence and James Matthews sites will continue until early 2015to test the efficacy of different reburial and stabilisation techniques and provide a comparative analysis of practical protocols. This work will be critical to the future development of national policy, 12 �methodology and technical guidelines for in-situ preservation and management of endangered historic shipwrecks. Acknowledgements The AHSPP is supported by the Australian Research Council through Linkage Partner Grant LP110200184. The Partner Organisations are: the Australian Government Department of Sustainability, Environment, Water, Population and Communities, the Victorian Department of Planning and Community Development, the Western Australian Museum, Australasian Institute for Maritime Archaeology, NSW Office of Environment and Heritage, Tasmanian Parks and Wildlife Service, Northern Territory Government, Queensland Department of Environment and Heritage Protection, the Norfolk Island Museum and the Australian National Maritime Museum. We are very grateful to our Partner Organisations and particularly their staff and to our phenomenal volunteers for contributing their time, expertise and equipment to the project. Bibliography Harvey, P., 1989.Excavation of the Shipwreck Clarence: Port Phillip Bay, October 1987.Unpublished Report. Victoria Archaeological Survey, Melbourne. Nystrom-Godfrey, I., Bergstrand, Y., and Petersson, H., (Eds.), 2011.Reburial and Analyses of Archaeological Remains – Phase II Results from the 4th retrieval in 2009 from Marstrand, Sweden. The RAAR Project, Bohusläns Museum and Studio VästSvenskKonservering, Uddevalla, Sweden. Richards, V., 2011.In-situ preservation – Application of a process-based approach to the management of underwater cultural heritage. In M. Staniforth, J. Craig, S.C. Jagoon, B. Orillaneda and L. Lacsina (Eds.),Proceedings of the Asia-Pacific Regional Conference on Underwater Cultural Heritage, 8-12 November 2011, Manila, Jericopim Publishing House, Manila: 769-785. Richards, V., Godfrey, I., Blanchette, R., Held, B., Gregory, D., and Reed, E., 2009.Insitu monitoring and stabilisation of the James Matthews site. In K. Straetkvernand D.J. Huisman (Eds.), Proceedings of the 10th ICOM Group on Wet Organic Archaeological 13 �Materials Conference, Amsterdam, 10-15 September 2007, RijksdienstvoorArcheologie, Cultuurlandschap en Monumenten (RACM), Amersfoort: 113-160. Biography Vicki Richards has been a Conservation Scientist in the Materials Conservation Department of the Western Australian Museum for the past 27 years. One of her primary research areas is devising and implementing appropriate on-site management plans for the long-term in-situ preservation of shipwreck sites. Ian MacLeod has extensive experience in the analysis and interpretation of corrosion products and in-situ corrosion measurements on historic shipwrecks and archaeological sites. His current role is Executive Director of the Western Australian Maritime Museum in Fremantle Peter Veth has directed numerous archaeological projects on the evolution of maritime societies in Australia, Maluku and East Timor. He has published widely on site formation models and heritage conservation strategies. He is Winthrop Professor of Archaeology at the University of Western Australia. 14 � Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Session 7: Preservation and Conservation of Wet Archaeological Materials and Site Management Subject The topic of the resource Interview with Session 7 chairs Vicki Richards and Jon Carpenter and links to the papers presented in the session. Description An account of the resource This session will focus on in-situ preservation and conservation management issues, conservation analyses and treatments, and applied conservation research of archaeological materials from freshwater, marine and wet terrestrial sites. The main purposes of this session are to encourage the exchange of ideas and practices as well as the development of conservation networks throughout the region. Presentations, posters and workshops are invited that address any of the following areas: • In situ preservation of marine archaeological materials, including reburial practices • Conservation management of shipwreck sites, including on-site monitoring • Conservation treatment case studies • Research into the analysis and treatment of wet archaeological materials • Review of the status of wet archaeological conservation programs in the Asia Pacific region • Development of collaborative conservation research and treatment programs Suggestions for additional topics are welcomed by the session organizers. Creator An entity primarily responsible for making the resource Vicki Richards and Jon Carpenter Document A resource containing textual data. Note that facsimiles or images of texts are still of the genre text. Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource The Australian Historic Shipwreck Preservation Project: In-situ preservation and long-term monitoring of the Clarence (1850) and James Matthews (1841)shipwreck sites Description An account of the resource Increasingly archaeologists are opting for on-site examination, reinterment and in-situ preservation of underwater cultural heritage sites as the first option in the management of sites at risk as opposed to the more traditional excavation, recovery, conservation and display/storage methods. This decision will inevitably be based on significance assessment, degree of perceived risk and resourcing issues. However, long-term monitoring must become an integral part of these management programmes in order to quantitatively evaluate the effectiveness of the in-situ preservation techniques employed. Absence of monitoring is equivalent to abrogation of responsible management and in some cases can be considered tantamount to cultural vandalism. In 2012 the Australian Historic Shipwreck Preservation Project (AHSPP) commenced, having secured funding through a substantial Australian Research Council Linkage Grant with 10 Australian Partner Organisations and three universities. One of the major aims of the project is to develop a protocol for the excavation, detailed recording and reburial of significant shipwrecks under threat, fostering a strategic national approach for the management of underwater cultural heritage sites at risk. Two historically significant shipwreck sites were chosen for this longitudinal comparative study – the Clarence (1850) located in Port Phillip Bay, Victoria and the James Matthews (1841) which lies in Cockburn Sound, Western Australia. Both sites have been preserved in situ using two very different but innovative remediation strategies. More importantly a long-term monitoring programme has been implemented which will characterise changes in the reburial environment and the effect on the reinterred materials. In this way, the efficacy of both in-situ preservation techniques will be systematically tested, providing a comparative analysis of practical protocols for the long-term protection and management of underwater archaeological resources. Creator An entity primarily responsible for making the resource Vicki Richards Ian MacLeod Peter Veth, in Van Tilburg, H., Tripati, S., Walker Vadillo, V., Fahy, B., and Kimura, J. (eds.) Date A point or period of time associated with an event in the lifecycle of the resource 5/15/2014 Asia-Pac Session 7 2014 https://apconf-much.org/proceedings/files/original/be8aef3ec298a4f6a487287c3b42be54.pdf 5515c2008cdb6c76aa9a6ac22451bbd8 PDF Text Text Scientific analysis and conservation of porcelain recovered from the Nanhai I in the South China Sea Nai-sheng Li, Xing-linTian, Zhi-guo Zhang, Da-wa Sheng, and Jing-nan Du Chinese Academy of Cultural Heritage 2 Gao Yuan Street Chao Yang District Beijing 100029 China Email: Lineas@126.com Abstract The Nanhai I is a merchant ship which sank in the South China Sea 800 years ago while transporting different kinds of precious porcelain and metal work. The Nanhai shipwreck is 30 m long wooden vessel lay in 25 m of water and was covered by fine sediment. Most of the porcelain artefacts are discs, bowls, vases and pots. Some of them were covered by thick encrustations. In this research, X-ray fluorescence energy dispersive X-ray (XRF-EDX) analysis and ion chromatography (IC) were employed to investigate the contaminants in these porcelains. Distilled water and alternating hot and cold cleaning were used to remove the harmful salts. Conductivity meter and ion chromatography were used to monitor the desalination processes. Based on these results, an appropriate method was selected to desalinate the porcelain from the Nanhai I shipwreck. Key words: Nanhai I shipwreck, Porcelain, Ion chromatography, XRF, EDX Introduction The Nanhai I was a Song Dynasty shipwreck located south of Dong Ping harbor, Yangjiang City, Guangdong Province, China. It was the first shipwreck excavated in China. The Nanhai I is 30.4 m long, 9.8 m wide and 4 m high (not including the mast) and has an estimated tonnage of 600. In 1987, a British marine exploration company found an ancient shipwreck from The Honorable East India Company, which was loaded with 6 cases of silver and 385.5 tons of fine ingots. In August 1987, the British Company applied to the State Administration of Cultural Heritage of China to salvage the shipwreck. Permission was granted and the salvage plan was carried out as a UKChina co-operative project. During this salvage project another ancient Chinese shipwreck site was located. It was named the Nanhai I. Since the discovery, the shipwreck site has been thoroughly investigated by underwater archaeologists. In 2007, 1 �the ship was successfully salvaged in strict accordance with underwater archaeology standards and placed in the “Crystal Palace” of the Maritime Silk-Road Museum of Guangdong. This work was innovative in the history of world underwater archaeology. According to the archaeological investigations conducted over the years and the results of two test excavations, the Nanhai I was loaded with 6000-8000 artefacts, the majority being porcelain. Most of the porcelain came from kilns in Zhejiang Longquan, Fujian Dehua and Jiangxi Jingdezhen. There were over 30 different kinds of porcelain identified; some of them could be classified as Country-level and secondary level based on their estimated value. Many examples had a strong Arabic style, which were identified as the “overseas processing orders” manufactured during the Song Dynasty. In addition, there were some gold items, lacquer-ware and metal artefacts on site. Some of the artefacts had suffered from prolonged seawater immersion and had been adversely affected by the calcareous cement formed by marine organisms and burial in the seabed for an extended period of time. These concretions incorporated many artefacts forming conglomerations of varying sizes (Wei, 2011). After excavation and recovery, due to changes in temperature and humidity, these concretions caused physical damage to the metal or porcelain artefacts incorporated in the conglomerations (Wei, 2012). Meanwhile, because of the high salt environment of the sea water, the porcelain contained high levels of salt. With changes in the local environment, dissolution and crystallization of the salts occurred causing spalling of the glazes. Therefore, it was extremely important that a procedure to safely extract the cultural relics from the concretions and desalinate the artefacts was found urgently. In this research, XRF-EDX analysis and IC were employed to investigate the contaminants in these porcelains. Based on the results from these analyses suitable chemicals were selected to remove the concretions. Distilled water and alternating hot and cold cleaning were used to remove the harmful salts. Conductivity meter and ion chromatographies were used to monitor the desalination processes. Based on these results, an appropriate method was selected to desalinate the porcelain from the Nanhai I shipwreck. 2 �Composition and soluble salt analysis Samples description Ten pieces of porcelain recovered from the Nanhai I were selected for the test analyses. The fragments chosen represent porcelain manufactured at the Jingdezhen Hutian, Dehua, Yaozhou and Cizao kilns from the Southern Song Dynasty and include bluish white porcelain, celadon, brown porcelain and many other varieties (Fig. 1 and Table 1). Instruments and Testing Prior to the desalination experiments, XRF-EDX and IC were used to characterize the chemical elements and ion concentrations in the porcelain samples recovered from the Nanhai I shipwreck. The conductivity meter and IC were used to monitor the desalination process. Constituent testing– XRF-EDX SHIMADZU EDX-800HS, XRF, Rhodium target (Rh), voltage: Ti-U 50kV; Na-Sc 15kV, the analyses were performed under vacuum for 200 seconds. The results are shown in Table 2-1. Soluble salts testing – IC To extract the soluble salts from the ceramics, more than 5g of Fig. 1: Images of the ten porcelain samples recovered from the each sample, normally a powder, Nanhai I.: (L. Naisheng). was mixed with 50 ml of de- ionized water in a 50 ml volumetric flask for more than 24 hours. The chromatograms were recorded with a Shimadzu SCL-10A ion chromatograph. Anions were analysed using a Shim-pack IC-SA3 (G) pre-column, a Shim-pack IC-SA3 column and an Anion Cartridge Suppressor; cations were analysed using a Shim-pack IC-SC3 (G) precolumn, a Shim-pack IC-SC3 column and a Cation Cartridge Suppressor. A Shimadzu CDD-10Asp conductivity detector and a Shimadzu LC Solution workstation were also used. The volume introduced into the injection valve of the instrument was normally 100 3 �µl and the loop volume was 60 µl. Automatic Science Instrument (Tianjin) F filters (0.22 µm-13 mm) were used to remove solid particles. The results are listed in Table 2-2. Conductivity meter The conductivity meter was a portable HANNA HI8733 model, multi-range conductivity/TDS meter with a built-in temperature sensor connected to a HI76302W four ring conductivity electrode. The temperature coefficient compensation is 2.5%/°C and the results of the desalination experiments are shown in Table 2 and 3 and Figs 3 and 4. Desalination of the porcelain Desalination methods The extent of preservation and the composition of the porcelain must be taken into consideration when interpreting the results of the desalination experiments. The number of porcelain artefacts recovered from the Nanhai I was enormous and there were many intact, unbroken objects. So it was decided to experiment with two solutions: 1. a static de-ionized water infusion at room temperature (25°C) and 2 heat the static de-ionized water (50°C) to accelerate the desalination process. The porcelain samples NH1-NH5 were used in this first experiment to select the most appropriate desalination method. Two similar sized pieces of ceramic were cut off from each porcelain sample (NH1NH5) and weighed accurately. One sub-sample was placed in the static de-ionized water at room temperature (200ml) and the other sub-section placed in the heated deionized water solution (200ml). These latter sub-samples were heated in a water bath to 50°C for 8 hours each day and then allowed to stand static for the rest of the time (Fig. Fig. 2: The desalination experiments for the porcelain samples NH1-NH5.: (L. Naisheng). 4 �2). After 24 hours all solutions were changed. After each change the solutions was measured using the conductivity meter and ion chromatography for a total of 21 days. The solutions were heated for 8 hours every day for 21 days. The results of the desalination experiments for NH1-NH5 are shown in (Fig. 3). Fig. 3: The daily variation in conductivity of the Fig. 4: The weekly variation in conductivity (µS) of the desalination solution for NH1~NH5.: (L. desalination solutions for NH6-NH10.: (L. Naisheng). Naisheng). The static de-ionized water infusion method was used to desalinate the other five porcelain samples, NH6-NH10, however the desalination time was extended from 1 day to 1 week and the volume of water increased to 4L. The conductivity results are shown in Table 2 and 3 and (Fig. 4). Results and Discussion XRF Analyses Based on the XRF-EDX data in Table 2-1, the major elements in the surface of the recovered porcelain are SiO2 and Al2O3, which is similar to the chemical composition of common undegraded porcelain in China. However there are still some significant differences. For example, the CaO, Fe2O3 and SO3 content is higher in the glaze of the porcelain samples, NH2, NH3, NH10, while the SO3 content is higher in the body of 5 �sample NH2 than other samples. The reason for the increase in these elements may be due to prolonged immersion in seawater. IC Analyses Based on the IC results in Table 2-2, there are many soluble ions present in the porcelain samples. The major ions are chloride (Cl-), sulfate (SO42-), sodium (Na+), potassium (K+), magnesium (Mg2+) and calcium (Ca2+), which are present in the seawater. The total salt content of each sample ranged from 1,000 ppm to 8,000 ppm. Such high concentrations of soluble salts will tend to recrystallise during changes in the environment and cause damage to the glaze and body of the porcelain, so an appropriate method to remove the soluble salts from marine porcelain is extremely important. Desalination of samples NH1-NH5 Based on the results in Fig. 3, the static de-ionized water infusion method and the heating method to accelerate the desalination process are both very effective and the rates of desalination for both methods are similar. After two days, the conductivity curve of the soak solutions of NH1-NH5 decreased significantly, which means the soluble salts (NaCl, MgCl2, etc.) in the facial layers had been removed. However, after 14 days, the conductivity increased, which indicates that there was still some soluble salts present deeper within the body of the porcelain. After this time the conductivity decreased and plateaued again after approximately 21 days. These results indicate that for the alternating hot and cold water soaked samples, the conductivity of the soak solutions plateaued after 15 days with the average conductivity being under 1μS/cm. This means the samples had almost reached the desalination end point after this short time period (Naisheng, 2012). The total desalination time for the Nanhai I shipwreck porcelain samples (NH1-NH5) was 25-30 days for the heated desalination method and 50-60 days for the static de-ionized water infusion method. Desalination of samples NH6-NH10 Fig. 4 shows that after 9 weeks of soaking, the conductivity of the better preserved porcelain samples like NH6, NH7 and NH9 were steady and the average values were under 1μS/cm (Naisheng, 2012), indicating the desalination process had reached its end point. However, for the porcelain samples NH8 and NH10, the conductivity was still 6 �around 2μS/cm (Naisheng, 2012), which was slightly higher than the better preserved samples indicating that these samples were more degraded and had therefore not reached their desalination end point after 9 weeks of immersion due to a higher initial salt content. Based on the results of these desalination experiments the static deionized water infusion method is an effective and convenient desalination method for the Nanhai I porcelain, especially for the better preserved samples, which easily reached their desalination end point after 63 days. Conclusions Based on the results of the XRF-EDX, IC and conductivity tests on the Nanhai I porcelain samples, the conclusions are as follows: 1. Based on the XRF-EDX analysis data, the major elements in the surface of the recovered porcelain are SiO2 and Al2O3, which is similar to the chemical composition of common, undergraded porcelain in China while the concentrations of CaO, Fe2O3 and SO3 are high and maybe due to their prolonged immersion in seawater. 2. IC analysis data shows that the total salt content of each sample ranged from 1,000 ppm to 8,000 ppm, and the main ions present are Na+, K+, Mg2+, Ca2+, Cl- and SO42-. Such a high content of soluble-salts within the samples will cause damage to the glaze and body of the porcelain. 3. The results of the desalination experiments indicate that the static de-ionized water infusion method is an effective and convenient desalination method for porcelain recovered from the Nanhai I shipwreck, especially for better preserved porcelain. They easily reached their desalination end point after 63 days. Acknowledgements We are grateful for the samples offered by the Curator Huang Tiejian and the Director Lin Tang'ou of the Guangdong Maritime Silk-Road Museum for analysis. This research was sponsored by the Chinese Academy of Cultural Heritage. References Naisheng, L., 2012. Scientific analysis and protection on ancient marine porcelains recovered from Huaguangjiao I in South China Sea. Science and Technological Research on Cultural Heritage, Vol. 8: 16-34. 7 �Wei, L., 2012. Research on the composition of the concretion encrusting on ancient marine iron. Science and Technological Research on Cultural Heritage, Vol. 8: 132-145. Wei, L., 2011. Scientific analysis of the concretion on ancient marine iron recovered from three shipwrecks in South China Sea. Journal of National Museum of Chinese History, Vol. 2: 148-151. Biography Naisheng Li received his PhD in 2006 from the USTC, Hefei, China. His research field comprises the analysis and conservation of museum objects and underwater cultural relics, such as porcelain, metals, stone, and wooden shipwrecks. Since 2006, he has worked as a conservation and research staff of ancient objects at the Chinese Academy of Cultural Heritage (CACH) in Beijing. He is currently participating in designing the conservation of Nan Hai No.1 Shipwreck. Number Vessel shape bowl(mouth rim） Characteristics Grey porcelain body, celadon glaze, pattern on the surface. NH2 fragment Grey porcelain body, glaze spalling. NH3 fragment Grey porcelain body, brown glaze. NH4 fragment Grey porcelain body, glaze spalling. NH5 fragment White porcelain body, white glaze dish White porcelain body, green white cracked glaze; there is a pattern of hemerocallis on the inner part of the porcelain Pulverization on the body section; fragile, easily broken. NH7 plate（ bottom) White porcelain body, green white glaze; carving on the inner part of the porcelain; there are five nail marks on the inner bottom of the porcelain. Brown sediment on the porcelain body; the glaze is yellow and part of it has black deposits. NH8 bowl（ bottom) Grey porcelain body, green glaze; carving on the inner part of the porcelain. Better extent of preservation; part of the glaze has white deposits. NH9 bowl（ mouth rim） Grey body, green glaze; the space between the body and glaze is wider than others. Glaze corroded; part of the glaze has peeled off; part of the glaze has black and brown deposits NH10 jar（ belly） Grey body, no glaze on the inner part but brown colored; the surface has brown glaze. Body is weak and most of the glaze has peeled off. NH1 NH6 Description Body corroded, pulverized and loose. Body corroded, very porous; sediment on the porcelain. The body is weak; the surface of the glaze is bumpy; part of the glaze has peeled off. The body is weak; the entire glaze has peeled off. Better extent of preservation; black deposits on the surface. Table 1: Description of the ten porcelain samples recovered from the Nanhai I.: (L. Naisheng). 8 �Number Na2O MgO Al2O3 SiO2 P2O5 SO3 K2O CaO TiO2 MnO Fe2O3 ZnO NH1body 2.69 0.67 19.77 68.67 0.10 1.43 3.11 0.29 0.44 0.04 2.74 0.02 NH2body 0.58 0.27 19.24 67.16 0.11 6.12 3.15 0.95 0.07 0.15 2.13 0.02 NH3body 0.19 0.51 23.86 67.01 0.00 0.27 3.12 0.41 0.71 0.11 3.73 0.02 NH4body 0.54 0.71 23.59 68.01 0.00 0.11 2.73 0.26 0.72 0.04 3.19 0.02 NH5body 0.20 0.31 17.49 71.75 0.12 0.18 3.45 5.60 0.06 0.02 0.72 0.01 NH1glaze 0.25 1.64 13.07 60.84 1.39 0.30 2.59 16.14 0.34 1.42 1.94 0.03 NH2glaze 1.15 0.58 12.42 37.11 0.79 22.33 1.96 10.09 0.27 0.58 12.67 0.03 NH3glaze 0.49 3.35 13.14 47.59 2.79 0.40 3.23 19.89 0.51 2.12 6.42 0.06 NH4glaze 0.41 0.61 26.48 61.80 0.08 2.13 3.21 0.25 0.92 0.04 3.95 0.01 NH5glaze 0.65 0.54 0.21 0.11 2.88 12.78 0.05 0.10 1.24 0.03 0.87 2.02 3.10 0.07 0.80 2.23 0.45 1.69 1.23 2.04 0.86 15.46 65.92 NH6body 22.42 70.63 HH7body 23.11 73.40 NH8body 24.61 69.48 NH9body 23.61 71.79 NH10body 26.47 69.20 1.19 0.21 NH6glaze 20.64 66.47 2.56 0.29 2.33 6.89 NH7glaze 23.61 63.84 2.60 0.54 2.13 6.04 NH8glaze 19.62 63.55 3.67 0.50 2.12 8.57 0.17 NH9glaze 24.01 68.00 2.22 4.50 0.07 NH10glaze 19.50 52.53 5.24 1.48 1.90 12.07 0.86 0.73 0.22 0.07 1.77 0.13 1.52 0.69 2.20 0.06 0.68 0.07 0.95 0.29 1.39 0.02 0.48 0.64 0.01 0.26 6.19 0.04 Table 2-1: The XRF-EDX results for the porcelains recovered from the Nanhai I (wt%).: (L. Naisheng). Number Cl- SO42- Na+ K+ Mg2+ Ca2+ NH1 493.05 809.13 611.02 NH2 1870.53 631.03 3887.56 400.03 434.95 538.63 NH3 1018.16 237.82 1947.14 260.86 180.59 268.29 NH4 497.17 141.40 862.06 72.98 130.45 98.98 NH5 106.87 73.22 307.99 41.23 95.93 233.94 NH6 493.67 380.95 322.95 52.94 40.25 47.06 NH7 182.28 351.46 487.89 46.14 10.61 113.84 NH8 371.78 382.68 316.03 46.14 37.83 74.63 NH9 136.18 272.00 125.72 46.14 8.30 39.22 NH10 527.85 296.06 644.75 89.50 80.39 119.95 100.17 190.32 342.80 Table 2-2: The IC results for the porcelains recovered from the Nanhai I (µg/g).: (L. Naisheng). 9 �Number 7days 14days 21days 28days 35days 42days 49days 56days 63days NH6 38.71 6.07 1.83 0.53 0.6 0.18 0.15 1.44 0.7 NH7 15.71 0.35 0.08 0.24 0.34 0.09 0.11 0.33 0.73 NH8 29.98 9.25 8.01 7.43 4.36 2.96 2.79 2.94 2.17 NH9 12.84 2.21 3.16 0.32 3.38 2.03 1.64 0.67 0.43 NH10 251.6 14.13 9.21 4.84 4.85 3.51 3.18 0.8 1.07 Table 2-3: The weekly variation in conductivity of the desalination solutions for NH6-NH10 (µS/cm).: (L. Naisheng). 10 � Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Session 7: Preservation and Conservation of Wet Archaeological Materials and Site Management Subject The topic of the resource Interview with Session 7 chairs Vicki Richards and Jon Carpenter and links to the papers presented in the session. Description An account of the resource This session will focus on in-situ preservation and conservation management issues, conservation analyses and treatments, and applied conservation research of archaeological materials from freshwater, marine and wet terrestrial sites. The main purposes of this session are to encourage the exchange of ideas and practices as well as the development of conservation networks throughout the region. Presentations, posters and workshops are invited that address any of the following areas: • In situ preservation of marine archaeological materials, including reburial practices • Conservation management of shipwreck sites, including on-site monitoring • Conservation treatment case studies • Research into the analysis and treatment of wet archaeological materials • Review of the status of wet archaeological conservation programs in the Asia Pacific region • Development of collaborative conservation research and treatment programs Suggestions for additional topics are welcomed by the session organizers. Creator An entity primarily responsible for making the resource Vicki Richards and Jon Carpenter Document A resource containing textual data. Note that facsimiles or images of texts are still of the genre text. Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Scientific analysis and conservation of porcelain recovered from the Nanhai I in the South China Sea Description An account of the resource The Nanhai I is a merchant ship which sank in the South China Sea 800 years ago while transporting different kinds of precious porcelain and metal work. The Nanhai shipwreck is 30 m long wooden vessel lay in 25 m of water and was covered by fine sediment. Most of the porcelain artefacts are discs, bowls, vases and pots. Some of them were covered by thick encrustations. In this research, X-ray fluorescence energy dispersive X-ray (XRF-EDX) analysis and ion chromatography (IC) were employed to investigate the contaminants in these porcelains. Distilled water and alternating hot and cold cleaning were used to remove the harmful salts. Conductivity meter and ion chromatography were used to monitor the desalination processes. Based on these results, an appropriate method was selected to desalinate the porcelain from the Nanhai I shipwreck. Creator An entity primarily responsible for making the resource Nai-sheng Li Xing-linTian Zhi-guo Zhang Da-wa Sheng Jing-nan Du, in Van Tilburg, H., Tripati, S., Walker Vadillo, V., Fahy, B., and Kimura, J. (eds.) Date A point or period of time associated with an event in the lifecycle of the resource 5/15/2014 Asia-Pac Session 7 2014 https://apconf-much.org/proceedings/files/original/db333a221a32866af0908e1f8529fbe5.pdf 2ce324676657651adfb93b7c0e6d837a PDF Text Text The construction of a simple sand dumping barge to aid reburial of a shipwreck site Jon Carpenter Western Australian Museum Department of Materials Conservation, Shipwreck Galleries, 45-47 Cliff St, Fremantle, WA, 6160, Australia E-mail: jon.carpenter@museum.wa.gov.au Jim Grehan and Jan Dols Marine Engineer volunteers c/o Department of Materials Conservation Shipwreck Galleries, 45-47 Cliff St Fremantle, WA, 6160, Australia Abstract A gradual and unremitting decrease in the level of the sand forming the seabed in which the wreck of the James Matthews (1841) lies buried (located in Cockburn Sound, Western Australia) became a cause for concern as progressive deterioration of the structures on the site was taking place. The situation led to the innovative use of linked medium density polyethylene Traffic Management Delineator barriers (Omni OB1800) to create a walled enclosure around the site into which sand could be reintroduced to bury exposed structures and prevent its subsequent dispersal, as would be the case if it were simply dumped over the wreck. The shallow, 2.5m depth of water over the wreck site restricted the possibility of delivering a substantial quantity of sand via a large vessel or barge. Commercial dredging and pumping of sand was also considered but financial constraints ultimately ruled out any of these options. The volume of sand required to fill the enclosed area was calculated to be 165 cubic metres. To improve the rate at which a reasonable amount of sand could be added to the enclosure a small budget ($2000 AUD) was provided by the Australian Historic Shipwreck Protection Project (AHSPP) for the Western Australian Museum’s team of retired, volunteer Marine Engineers to design and construct a 3m x 4m sand dumping barge. Costs incurred were mainly for the steel framework and floor components of the barge as they required materials of specific dimensions. A small boat winch and pulley were also specific purchases. Floatation was provided by fourteen steel drums (each 200 litre capacity), which were obtained gratis. Note no labour costs were incurred to construct the barge. 1 �Key words: barge, sand dumping, steel, construct, drums, reburial. Introduction The wreck of the James Matthews (1841) is located in shallow water close to Woodman Point in Cockburn Sound and not far from the Port of Fremantle in Western Australia (Henderson, 2009). At the time of discovery, in the early 1970’s, thesite was completely buried in sand except for one or two small concretions noticeable in the seagrass and a few pieces of scattered roofing slate that proved to be a part of the vessel’s cargo. Excavation of the wreck site, not long after it was found, was extensive and reburial with the dredged overburden undertaken but the level of sand coverage was not completely satisfactory. The loss of extensive areas of seagrass over the years, that in part, afforded some stability to the sands that buried the James Matthews, have prevented the natural build-up of sediment at the site. Over the last few years it has become apparent that structures on the wreck site are deteriorating as they have become progressively more exposed. The nearby activities (approximately 300 m away) of a dredging arm operating off the end of a reclaimer jetty, used to recover shell dredged further out to sea that is regularly dumped by barges, has created an extensive depression (12 m deep) in the seabed. This ‘hole’ and the associated barge channel leading to it have possibly contributed to a general decrease in the level of the nearby seabed, with its consequent impact on the wreck site, as sand in the vicinity gravitates towards these depressions. To rebury most of the exposed structure at the James Matthews site it was determined that a depth of at least 0.8 metres of sand was necessary. Sandtrapping mesh covers have been previously trialled with success on parts of the site but an assessment of the overall area to be covered and the elevation of the structures within it implied that mesh alone was unlikely to be appropriate for total 2 �reburial. The situation led to the innovative use of 36 linked Traffic Management Delineator barriers (Omni OB1800), made of medium density polyethylene, to create a walled enclosure around the site into which sand could be reintroduced to bury exposed structures and prevent its subsequent dispersal, as would be the case if it were simply dumped over the wreck. For more information about the James Matthews and the Australian Historic Shipwreck Protection Project readers are referred to the papers in these conference proceedings by Richards et al. (2014) and Shefi et al. (2014) Methodology The shallow 2.5 metre depth of water over the James Matthews wreck site restricted the possibility of delivering a substantial quantity of sand via a large vessel or barge. Commercial dredging and pumping of sand was also considered but financial constraints ultimately ruled out any of these options. The volume of sand required to fill the enclosed area to the recommended height of 0.8m was calculated to be 165 cubic metres. To improve the rate at which a reasonable amount of sand could be added to the enclosure a small budget ($2000 AUD) was provided Historic by the Australian Shipwreck Protection Project (AHSPP) for the Western Australian Museum’s team of retired, Engineers volunteer to Marine design and construct a 3 x 4 metre sand dumping barge (overall dimensions actually 3050mm x 3900mm). Costs incurred were mainly for the steel framework Fig. 1: The completed sand barge when first launched. (J. and floor components of the Carpenter). barge as they required materials of specific dimensions. A small boat winch and 3 �pulley were also specific purchases. Fourteen steel drums (each 200 litre capacity) were used in the construction, all of which were obtained gratis. Four drums were positioned vertically essentially halving the depth to which they would submerge and therefore halving their effective floatation capacity resulting in an overall buoyancy equivalent to twelve drums. Note no labour costs were incurred in the construction of the barge (Fig. 1). Construction and Operation. The sand barge proposal for the James Matthews reburial project started out with a basic sketch comprising a series of 200 litre drums, arranged in a rectangular formation, including a floor that incorporated two doors, a locking mechanism and a raised-frame structure from which to operate a pulley system for closing the doors after sand was discharged. It was initially envisaged that the ends of the drums would be simply welded together, as a cost saving measure, although this didn’t immediately address the issue of joining the drums at the barge corners. The museum’s team of volunteer Marine Engineers had the necessary skills and tools to construct the barge and would provide a free design process and labour. Construction was to be carried out using welded and bolted mild steel. Due to time constraints during its manufacture the non-galvanized metal parts of the barge were only painted with a corrosion inhibiting zinc undercoat. The engineers advised against direct end to end welding of the drums in favour of constructing a framework into which individual drums could be placed and replaced if no longer airtight. The dual doors were omitted in favour of a single central door. This was done to simplify its construction and operation but importantly to avoid the possibility of one door not operating in unison with the other and potentially resulting in the barge tipping over from the weight of the sand remaining on one side. 4 �The project began with the welded assembly of four individual outer frames made from angle iron (100mmx 100mm) designed to hold two horizontal drums on each of the fore and aft frames(1940 mm x 540 mm) and three horizontal drums and later two vertical drums on each side frame (3850 Fig. 2: The four outer frames with strapped drums installed. (J. mm x 540 mm). Flat steel Carpenter). retaining straps (50mmx3mm) were rolled to conform to the curvature of the drums and welded in place to fit across each frame. A detachable set of the curved straps, each with a screw threaded rod welded on the ends, were made to mate with corresponding holes to bolt the drums to the frame (Fig. 2). As the horizontal drums at the corners of the barge could not be joined easily it was decided to mount an extra drum vertically at each corner. This also presented a curved surface and therefore cleaner ‘entry’ to the sea when the barge would be under tow and added the equivalent of an extra two drums to the overall buoyancy. The vertical drums Fig. 3: The main frames and door in position in preparation to were mounted on extensions to install the floor sections either side (assembly is inverted). (J. Carpenter). the side frames, the base of the drum resting on a flat bar welded to form a triangle at each of the four corners. 5 �Each corner drum was secured by threaded rods (15mm diameter) bolted through the extended frame and through a steel cross-strap positioned on top of each drum. All other nuts/bolts used to assemble the barge were 10mm in diameter. At this stage the four main drum frames (sides and ends, with drums temporarily removed) were bolted to a welded rectangular-shaped central frame (1800mm x 2750mm), made from angle-iron(100mmx 100mm)that was to become the framework for the barge floor incorporating the door. The floor/door frame and frame of the actual door (800mm x 2750mm) were made from welded square section steel tube (75mm x 75mm). The open ends of the tube were fitted with cover plates and welded to be air-tight. To provide a strong floor and improve overall rigidity of the construction, steel ‘C’ section purlins (galvanized) were used (200mm x 75mm x 2mm). The purlins were cut into short lengths and the ends welded to each side of the frames and to each other. This further improved floor strength and the overall rigidity of the barge (Fig. 3). To prevent sand dropping through any small gaps between various spot welded areas of the floor and door they were filled with silicon gap filler. The larger gap in the floor along the hinged side of the door was covered with a strip of sheet rubber adhered with contact cement onto the fixed portion of the floor frame. The hinge for the door was made from a single length of steel rod (20mm diameter)mounted through drilled steel brackets welded alternately to the floor and door frames. This hinged shaft was prevented from sliding out of the brackets by securing it with locking pins incorporating washers to minimise rubbing and wear. The catches holding the door in the closed position operate by rotation of a second full length steel rod, mounted in similar drilled brackets, possessing three welded lugs that come to bear and hold against a flat overlapping steel lip welded along the closing side of the door. This lip laps over the adjacent floor frame and prevents the door from being raised above its fully-closed position. The lip also helps to prevent sand loaded into the barge from dropping through the clearance gap for the door. The door locking shaft is prevented from slipping out of its 6 �mounting brackets by the door locking lugs as each of the three lugs is rotated between two brackets welded to the floor frame. One end of the locking shaft has a right-angle lever welded to it that almost horizontally aligns with a welded ‘U’shaped bracket when the door is in the closed position. The ‘U’ bracket retains a steel ring of sufficient internal diameter for it to slide along the bracket and simultaneously over the door locking lever. This is achieved by applying downward hand-pressure on the lever to bring it into a parallel position with the bracket. Once released the lever locks the ring in place as it attempts to spring back to its former position. To open the door the ring is struck with a long-handled hammer until it drops off the lever (and is retained by the bracket) and the weight of sand on the barge floor forces the door to open. As the door drops down the actuating lever rapidly goes up in the opposite direction (Note this is a safety concern and the person releasing the lever must keep well clear of the lever and descending door). To raise the door and temporarily hold it closed, a small ratchet type boat winch with a stainless steel cable, attached by a shackle to the door, is mounted on a bracket attached to a tripod frame with a pulley wheel fitted to its apex. The ratchet system allows the winch to hold the door in the closed position in order for the lever locking ring to be re-engaged. The winch was inexpensive and its pulling capacity (500 kg) and gear ratio (3:1) more than sufficient to raise the door but it was not intended that it be used to hold the weight of a load of sand. Before the door is opened with a load of sand the winch ratchet must be disengaged to allow the winch to free-wheel and the cable to run out (Note this was a safety concern as the winch handle could not be detached and its rapid rotation seen as a potential risk to the operator who must keep well clear until the door is released and it has to be raised again). 7 �During the construction process the sheer weight of the main components of the sand barge (~700kg), particularly the central frame with its floor and door, presented handling issues both during its manufacture and its physical loading and unloading from the truck at the deployment area. Although it is possible to lift and carry parts of the barge separately albeit with 8 to 10personnel and then assemble it on-site, it is recommended that a truck with a HIAB crane be hired to load the barge in one piece onto the truck and then unload the barge directly into the water. This method of deployment was used when the sand barge was reassembled a second time to dump the remaining sand after the main fieldwork phase had concluded. Field Operation Fig. 4: Manoeuvring the loaded sand barge into position. (J. Carpenter). Initially, during the main fieldwork phase, the sand barge was physically handled as separate components as it was too wide to fit on the tray of the museum’s truck when fully assembled. The components were very heavy and required 8-10 personnel to manually lift and manoeuvre. The disassembled sand barge was delivered to a boat ramp where the barge was unloaded, the floor section placed on a four wheeled support frame, the remaining components bolted to it, the drums installed and the barge launched down the ramp restrained by a rope. The fourteen drums provided adequate buoyancy despite some initial concern that the weight of the overall framework and particularly the floor with its door was excessive. To minimise the possibility for metal fatigue and/or loosening of the retaining bolts, caused by any rocking motion of the corner drums when the barge was underway, 8 �a rope was secured around the drums to minimise any unwanted movement. A tow rope was attached to two shackles fixed near the corners of the bow and the barge towed to the sand loading area. Initially clean, washed proprietary sand was physically loaded into the barge via sand bags (maximum weight 20 kg) Fig. 5: The door opening to release a load of sand onto the directly from a nearby beach and James Matthews site inside the wall of barriers. (J. Carpenter). then subsequently from a larger boat moored adjacent to the wreck site. The loaded barge was not difficult to manoeuvre over the wreck site using a combination of small boats and ropes then, aided by snorkelers, it was easily moved into its final position for discharging the load of sand (1.0 - 1.5 ton) (Fig. 4). The hammering of the ring to release the door and its re-locking was performed by a snorkeler using the procedure described in the Construction and Operation section of this paper (Fig. 5). A second snorkeler disengaged the ratchet on the winch before the door was released and re-engaged the ratchet to close the door after all the sand was removed from the barge. As the single door is centrally Fig. 6: Snorkelers removing sand not directly released when Carpenter). 9 the door opened. (J. �located and it does not cover the entire floor a ledge of fixed floor (480 mm wide) on either side retained sand that snorkelers easily removed by hand (Fig. 6). At the end of the day the barge was left moored over the James Matthews site,, two solar cell charged lamps were attached as riding lights to warn fishers in small boats should they be travelling in the vicinity of the wreck at night. Conclusion In operation the sand barge performed very well. In the restrictive circumstances of budget constraints and the shallow water situation of the James Matthews wreck site the barge provided a means of delivering a reasonable quantity of sand with each load (1.0-1.5 ton). The overall amount of sand delivered to the site at this stage of the project is 20 m3 or 30 ton, which is the equivalent of about 5-10cm of sand coverage over the entire site. Obviously significantly more sand is required, however due to the sand barge’s robust construction an idea that was perhaps, initially, conceived as a basic and relatively cheap construction, to be used only once and then disposed of, is currently held in storage for future use. Acknowledgements The Marine Engineers team comprises of eight retired marine engineers and their manager, Richard Garcia. The two persons, Jim Grehan and Jan Doles, engaged full-time in the barge manufacture, are listed as main contributors to this paper. The additional contribution of the other team members, however small, is still considered significant and is hereby gratefully acknowledged. References Henderson, G., 2009. Redemption of a Slave Ship. The James Matthews. Western Australian Museum, Perth. Richards, V., MacLeod, I. and Veth, P., 2014. The Australian Historic Shipwreck Preservation Project – In-situ preservation and long-term monitoring of the Clarence (1850) and James Matthews (1841) shipwreck sites. In S. Tripati and V. 10 �Walker (Eds.), Proceedings of the 2nd Asia-Pacific Regional Conference on Underwater Cultural Heritage, 12-16 May 2014, Honolulu, Hawaii, Hawaii. Shefi, D., Veth, P., Philippou, C., Rodrigues, J., Richards, V. and Harvey, P., 2014.The Australian Historic Shipwreck Preservation Project – interim progress report. In S. Tripati and V. Walker (Eds.), Proceedings of the 2nd Asia-Pacific Regional Conference on Underwater Cultural Heritage, 12-16 May 2014, Honolulu, Hawaii, Hawaii. Biography Jon Carpenter is a conservator with 40 years of experience working principally with maritime archaeological materials at the Department of Materials Conservation, Western Australian Museum. The work performed is mainly with iron objects recovered from marine sites and he has conserved cannon from the earliest known shipwreck in Australia, the Trial (1622) and from HMS Sirius(1790), the Principle Escort of the First Fleet transporting colonists to Australia in 1788. As a diver and conservator operating in the field he conducts pre-disturbance assessments of shipwreck sites, including digital photography/video and on-site conservation of recovered artefact material. 11 � Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Session 7: Preservation and Conservation of Wet Archaeological Materials and Site Management Subject The topic of the resource Interview with Session 7 chairs Vicki Richards and Jon Carpenter and links to the papers presented in the session. Description An account of the resource This session will focus on in-situ preservation and conservation management issues, conservation analyses and treatments, and applied conservation research of archaeological materials from freshwater, marine and wet terrestrial sites. The main purposes of this session are to encourage the exchange of ideas and practices as well as the development of conservation networks throughout the region. Presentations, posters and workshops are invited that address any of the following areas: • In situ preservation of marine archaeological materials, including reburial practices • Conservation management of shipwreck sites, including on-site monitoring • Conservation treatment case studies • Research into the analysis and treatment of wet archaeological materials • Review of the status of wet archaeological conservation programs in the Asia Pacific region • Development of collaborative conservation research and treatment programs Suggestions for additional topics are welcomed by the session organizers. Creator An entity primarily responsible for making the resource Vicki Richards and Jon Carpenter Document A resource containing textual data. Note that facsimiles or images of texts are still of the genre text. Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource The construction of a simple sand dumping barge to aid reburial of a shipwreck site Description An account of the resource A gradual and unremitting decrease in the level of the sand forming the seabed in which the wreck of the James Matthews (1841) lies buried (located in Cockburn Sound, Western Australia) became a cause for concern as progressive deterioration of the structures on the site was taking place. The situation led to the innovative use of linked medium density polyethylene Traffic Management Delineator barriers (Omni OB1800) to create a walled enclosure around the site into which sand could be reintroduced to bury exposed structures and prevent its subsequent dispersal, as would be the case if it were simply dumped over the wreck. The shallow, 2.5m depth of water over the wreck site restricted the possibility of delivering a substantial quantity of sand via a large vessel or barge. Commercial dredging and pumping of sand was also considered but financial constraints ultimately ruled out any of these options. The volume of sand required to fill the enclosed area was calculated to be 165 cubic metres. To improve the rate at which a reasonable amount of sand could be added to the enclosure a small budget ($2000 AUD) was provided by the Australian Historic Shipwreck Protection Project (AHSPP) for the Western Australian Museum’s team of retired, volunteer Marine Engineers to design and construct a 3m x 4m sand dumping barge. Costs incurred were mainly for the steel framework and floor components of the barge as they required materials of specific dimensions. A small boat winch and pulley were also specific purchases. Floatation was provided by fourteen steel drums (each 200 litre capacity), which were obtained gratis. Note no labour costs were incurred to construct the barge. Creator An entity primarily responsible for making the resource Jon Carpenter Jim Grehan Jan Dols, in Van Tilburg, H., Tripati, S., Walker Vadillo, V., Fahy, B., and Kimura, J. (eds.) Date A point or period of time associated with an event in the lifecycle of the resource 5/15/2014 Asia-Pac Session 7 2014