Video interview with Session 7 chair Vicki Richards and Jon Carpenter.
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.
Ian Godfrey, Vicki Richards, and Debra Shefi
6/11/2014
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
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.
Adele Zubrzycka
Anthony J. Barham
Ulrike Troitzsch, in Van Tilburg, H., Tripati, S., Walker Vadillo, V., Fahy, B., and Kimura, J. (eds.)
5/15/2014
Research on the removal of calcareous and iron concretions from marine finds
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.
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.)
5/15/2014
Study of the corrosion of copper coins from the wreck of “The South China Sea No.1â€
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.
Xing-ling Tian
Nai-sheng Li
Zhi-guo Zhang, in Van Tilburg, H., Tripati, S., Walker Vadillo, V., Fahy, B., and Kimura, J. (eds.)
5/15/2014
The Australian Historic Shipwreck Preservation Project – interim progress report
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.
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.)
5/15/2014
The Australian Historic Shipwreck Preservation Project:
In-situ preservation and long-term monitoring of the Clarence (1850) and James Matthews (1841)shipwreck sites
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.
Vicki Richards
Ian MacLeod
Peter Veth, in Van Tilburg, H., Tripati, S., Walker Vadillo, V., Fahy, B., and Kimura, J. (eds.)
5/15/2014
Scientific analysis and conservation of porcelain recovered from the Nanhai I in the South China Sea
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.
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.)
5/15/2014
The construction of a simple sand dumping barge to aid reburial of a shipwreck site
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.
Jon Carpenter
Jim Grehan
Jan Dols, in Van Tilburg, H., Tripati, S., Walker Vadillo, V., Fahy, B., and Kimura, J. (eds.)
5/15/2014