Underwater Sites Research Articles

Drowning the Pompeii premise: frozen moments, single events, and the character of submerged archaeological sites

ABSTRACT The archaeology of inundated cultural landscape sites is not new and is an important component of the global record, yet these sites are distinct from shipwrecks and other site types underwater. Just as on land, underwater sites are subject to a dynamic range of formation processes, which must be analytically controlled. However, there are lingering misconceptions about underwater sites, specifically how they are formed, how much has been preserved, and their contribution to the broader field of archaeology. This paper discusses issues of preservation, context, and formation processes using misunderstandings of the Pompeii premise in underwater research as a conceptual guide. Ultimately acknowledging that, just as on land, archaeological sites underwater are diverse and unique, with site-specific pre- and post-depositional transformations. Different sites supplement each other, and the unique preservation underwater makes them a particularly valuable complement to the terrestrial record and a vital part of world archaeology.

Submerged inland landscapes of the Aucilla basin, Northwest Florida, USA: populating the Late Pleistocene and Early Holocene landscape

ABSTRACT Archaeological data have demonstrated that modern Florida was occupied by at least 14,550 years ago, but evidence of Late Pleistocene and Early Holocene peoples (ca. 14,600–8,000 cal B.P.) is limited to far inland and upland settings, as more than half of Florida’s peninsula was drowned between ca. 21,000–6,000 cal B.P. Rising aquifer levels of the Late Pleistocene allowed some interior sites to preserve within forming river channels, especially some springfed sinkholes that became the Aucilla River of northwest Florida. Terrestrial sites are poorly preserved in comparison, containing stone tools in mixed and/or undateable stratigraphy. Geospatial analysis of the 92 early sites in the Aucilla basin demonstrates that the underwater sites are crucial to provide a more robust understanding of early people, as the earliest sites are found only underwater, and the preponderance of the multicomponent sites also are inundated.

Methods and Techniques of Photogrammetric and Topographic Geopositioning Applied to the Archaeological Record of Underwater Sites in Submerged Caves. The Cave of the Font De Ses Aiguades (Alcúdia, Mallorca)

Methods and Techniques of Photogrammetric and Topographic Geopositioning Applied to the Archaeological Record of Underwater Sites in Submerged Caves. The Cave of the Font De Ses Aiguades (Alcúdia, Mallorca)

Shipping metal: Characterisation and provenance study of the copper ingots from the Rochelongue underwater site (Seventh–Sixth century BC), West Languedoc, France

The copper ingots from the underwater site off Rochelongue, near Cap d’Agde, on the coast of West Languedoc, offer an exciting means to investigate coastal mobility and cultural interaction between southern France and the broader western Mediterranean basin in the Early Iron Age. This paper presents the results of elemental and lead isotope analyses of a selection of copper ingots from the Rochelongue site, along with several ingots from the Iberian Peninsula, and for the first time demonstrates that their composition is consistent with Iberian and Alpine metalliferous mineral sources, and possibly some Mediterranean sources as well. The Rochelongue site also speaks to the likely role of indigenous societies of Languedoc in the movement of metals between Atlantic, Continental and Mediterranean circuits. The Rochelongue ingot metal thus provides a window into expansive networks of trade contacts that must be evaluated alongside typological and cultural data.

Dive in the Past: A Serious Game to Promote the Underwater Cultural Heritage of the Mediterranean Sea

In the last decades, the popularity of video games has been increasing thanks to their unique ability to engage their audience and create empathy. Among them, serious games have additional purposes besides entertainment, such as learning and behaviour change. Serious games, in fact, have been successfully applied to different fields, including education, health, tourism, and cultural heritage. In this context, the paper describes a novel serious game developed for increasing awareness and promoting the Underwater Cultural Heritage (UCH). In particular, the paper focuses on the Dive in the Past Serious Game which allows users to simulate a virtual dive into the Mediterranean Sea to explore accurate and life-sized 3D reconstructions of underwater archaeological sites. The purpose of the game is twofold: to engage diver and non-diver tourists into a virtual interactive exploration of underwater sites through digital storytelling and challenges; to increase awareness and knowledge on Mediterranean UCH. This work has been carried out in the context of the MeDryDive project, an EU co-funded under the COSME Programme, which aims to create personalized dry dive experiences for the promotion of Mediterranean UCH sites as distinctive tourism destinations.

Oceanographic conditions in HMAS perth maritime conservation area, Serang Regency, Banten Province

The efforts to protect underwater sites such as shipwreck sites by assigning them as Maritime Conservation Areas are needed because they are limited, non-renewable and fragile cultural heritage. The location of the battleship HMAS Perth is one of the underwater shipwreck sites in Banten Bay waters. Several sites of other sunken warships and merchant ships are currently in Banten Bay waters. HMAS Perth designated as a Maritime Conservation Area on February 28, 2018, through the Ministry of Marine Affairs and Fisheries Decree No. 21/KEPMEN-KP/2018. The Central Government and Regional Governments carry out the management. One of the efforts to map the environmental conditions in the area is to carry out biophysical monitoring activities, including oceanographic conditions. Observations of oceanographic parameters were focused on the HMAS Perth ship site area and were covering nine stations. The parameters observed were depth, sea surface temperature, pH, DO, TDS, conductivity, and salinity. Observations show that the depth HMAS Perth Maritime Conservation Area ranges from 31.60-44.65 meters, the measurement of sea surface temperature showed a value of 30.4-31.2 °C. The pH concentration indicates that the waters are in acidic conditions, while the DO concentration was in the range of 5.95-6.94 mg/L. The TDS value at nine stations has an average value at six stations was 24 mg/L, while two stations showed an average of 5 mg/L. The salinity concentration found around 25-35 ppt, and the conductivity values have been ranges 38.6-40.1 mS/cm. Overall, the oceanographic conditions HMAS Perth Maritime Conservation Areas are suitable and meet the marine quality standards following the Minister of Environment Decree No. 51/2004 to survive the marine organism.

From Discovery to Public Consumption: The Process of Mapping and Evaluating Underwater Cultural Heritage in Malta

The in situ promotion and preservation of underwater cultural heritage sites is one of the main ideas of the UNESCO Convention on the Protection of Underwater Cultural Heritage. Currently, most shipwrecks are found in water shallower than the 50 m contour. The continued technological advances and increases in technical diving and deep-water exploration point towards a shift in this statistic, which is set to increase exponentially in the not-too-distant future. Thus, it is imperative to look at ways in which such directives can be implemented. This paper will highlight the synergy between existing remote sensing technologies and the management of underwater cultural heritage with examples of on-going research projects, such as Malta’s approach to surveying and implementing a scoring system for historic wreck sites based on local and global considerations of historic and natural conditions of site elements. Such an approach allows for the scaling of sites based on a number of parameters and provides instructive information for the creation of management strategies. The intention here is to demonstrate how large-scale remote sensing surveys can make major contributions to site management, which, in turn, facilitates the decision-making process in terms of how and what information is transmitted to divers and members of the public.

Locating submerged prehistoric settlements: A new underwater survey method using water-jet coring and micro-geoarchaeological techniques

In the past few decades the field of submerged prehistory has produced important data highlighting ancient coastal habitation across the globe. Most prehistoric underwater sites are discovered by chance (e.g., by industry, fishermen or recreational divers). New methods for detecting submerged prehistoric settlements have been developed using sophisticated remote sensing devices, yet with limited success. Simple, practical, and inexpensive methods for locating submerged settlements remain rare. Over 60 years of underwater archaeology and submerged prehistory in Israel, specifically along the Carmel coast, has led to a model for locating and studying submerged settlements, based on sand removal by storms. This study aimed to take this model a step further by developing a new, inexpensive method to identify, locate and characterize submerged sites. We collected undisturbed paleosol cores from exposed areas as well as under a few meters of sand, using a newly developed water-jet core sampling system. The cores were analyzed using micro-geoarchaeological techniques initially developed on terrestrial sites. The rationale behind this methodology is based on established knowledge that where human settlements occur, sediments are enriched by specific mineralogical signatures (e.g., heated clay minerals) and anthropogenic micro-remain assemblages (e.g., phytoliths, ash pseudomorphs and dung spherulites). Additionally, micromorphology can assist in identifying micro-stratigraphic patterns typical of human settlements. We tested sediment cores in three underwater contexts: a) exposed prehistoric surfaces within two known Neolithic sites (Atlit-Yam and Neve Yam), b) exposed paleosols without visible archaeological remains (serving as a control), and c) as a blind test, a buried paleosol currently covered by 1–3 m of sand, where the existence of a site is unknown. In the cores taken from the exposed Neolithic settlements, the micro-geoarchaeological characterization showed clear anthropogenic signals (typical mineralogy, elevated micro-remain concentrations, micro-stratigraphy). In the paleosol control cores, there was an absence (or negligible presence) of anthropogenic signals. The ‘blind test’ at the sand-covered locality revealed sediments without anthropogenic enrichments (similar to the control paleosols), thus suggesting the absence of a submerged settlement in this specific location. The new method is time- and cost-effective and can easily be applied worldwide along the shallow continental shelf as well as in deep water. The new method will facilitate discovery of new underwater sites and provide selection criteria (e.g., where the highest anthropogenic signal exists) for investment in underwater excavations. Additionally, it can be used to check for anthropogenic signals in buried locations detected by remote sensing, and to understand the spatial organization of submerged sites.

The integrated cultural landscape of North Gidley Island: Coastal, intertidal and nearshore archaeology in Murujuga (Dampier Archipelago), Western Australia

Recent studies conducted in Murujuga Sea Country have confirmed that Indigenous Australian archaeology does not end at the modern shore. Since the earliest peopling of the Australian continent, sea levels have fluctuated significantly, dropping as much as 130 m below modern mean sea-level during the Last Glacial Maximum (LGM). During this period, the continent (including Australia and New Guinea) represented a landmass one-third larger than present day Australia. As sea levels rose following the LGM, this extensive cultural landscape was inundated. The recent reporting of archaeological remains in a submerged context at Murujuga has enabled an integrated analysis of the archaeological landscape, based on direct evidence from archaeological sites that were originally formed on dry land, but are now located in intertidal and submerged environments. This study applies a landscape analysis centred on the submerged Cape Bruguieres channel site, and the Gidley Islands, where submerged, intertidal and coastal archaeology has been recorded. Aerial, pedestrian, and intertidal archaeological surveys were conducted to investigate the onshore and offshore landscape, providing new evidence with which to place the stone artefacts in the Cape Bruguieres channel into a wider context. Rock art engravings, grinding patches, quarries and upstanding stones – some of which are in the intertidal zone – point to the use of a landscape that is now submerged and to the possibility of discovering new underwater sites. By integrating evidence from subtidal and intertidal contexts with the onshore record, we explore the cultural landscape above and below the ‘waterline’ as a continuum.

Underwater Cultural Heritage in Asia Pacific and the UNESCO Convention on the Protection of the Underwater Cultural Heritage

Underwater cultural heritage (UCH) is a precious part of humanity’s shared history and heritage as it provides vital evidence and information about the interaction of humans with oceans, lakes and rivers. The Convention on the Protection of the Underwater Cultural Heritage was adopted by the General Conference of UNESCO (United Nations Educational, Scientific and Cultural Organization) in 2001 to protect this heritage which has become significantly vulnerable to threats such as pillaging, commercial exploitation and the development of the seabed with the evolution of marine technology in the latter half of the 20th century. The Convention celebrates its 20th anniversary in 2021 and has been ratified by 68 countries. Its annex, which provides rules about the activities directed at UCH, has become a major reference and is recognised as the established scientific standard for underwater archaeology and research today. Despite the growing recognition and application by the international community, the Convention has been ratified only by four countries in the Asia-Pacific region. Many underwater sites and shipwrecks have been commercially salvaged, particularly in Southeast Asia, and numerous artefacts recovered from the sites were often put up for auction, leading to irrevocable damage and loss of this valuable cultural heritage to future generations. This article as one of the themed articles dedicated to the UCH in Asia Pacific argues the roles of the Convention and the challenges and opportunities for the protection of UCH particularly in Southeast Asia. UCH contributes to the achievement of the Sustainable Development Goals and can play an important role in sustainable community and economic development. Its values and importance deserve to be widely recognised and advocated. Efforts for safeguarding cultural heritage in Asia Pacific needs to be pursued and enhanced through joining the 2001 Convention and with international support and cooperation.

A novel Structure from Motion-based approach to underwater pile field documentation

This article presents a novel methodology to the underwater documentation of pile fields in archaeological lakeside settlement sites using Structure from Motion (SfM). Mapping the piles of such sites is an indispensable basis to the exploitation of the high resolution absolute chronological data gained through dendrochronology. In a case study at the underwater site of Ploča, Mičov Grad at Lake Ohrid, North Macedonia, nine consecutive 10 m2 strips and a 6 m2 excavation section were uncovered, the situation documented, and the wood piles sampled. The gained data was vectorized in a geographic information system. During two field campaigns, a total of 794 wooden elements on a surface of 96 m2 could be documented three-dimensionally with a residual error of less than 2 cm. The exceptionally high number of fishes in the 5 m deep water resulted in a significant covering of potentially important information on the relevant photos. We present a machine learning approach, especially developed and successfully applied to the automatic detection and masking of these fishes in order to eliminate them from the images. The discussed documentation workflow enables an efficient, cost-effective, accurate and reproducible mapping of pile fields. So far, no other method applied to the recording of pile fields has allowed for a comparably high resolution of spatial information.

Submergence of the Western Greco-Roman Archaeological Site at the Eastern Harbor of Alexandria: Emerged from High Resolution Geophysical Mapping

Marine geophysical surveys were carried out at the underwater site in the south-western sector of the Eastern Harbor of Alexandria, opposite to the Egyptian Sea Scout Club. Survey works aimed to detect and study the surface and subsurface geomorphological changes caused by historic sea-level rise and natural hazards, by integrating the results of high-resolution geophysical mapping for the seafloor textures and the subsurface layers with previously published core data and sea-level records, the survey works employed echo-sounder, side scan sonar, and sub-bottom profiler. Acoustic data were ground-truthed using an ROV camera and sediment grab sampler. Results of bathymetric mapping and sonar imaging outlined two breakwaters and quay corresponding to a submerged ancient port; also, sediment types were classified according to variation in the magnitude of the backscattered intensities. Interpretation of sub-bottom profiles illustrated the depositional sequence of the topmost sedimentary layers where the sediment thicknesses were thickened by rates that perfectly matched with the recorded sea-level rise rate during the last two millennia, as indicated by isopach maps. Anthropogenic activities were noticed in particular outcropping areas on the sub-bottom profiles. The results explained the role of natural hazards and sea-level rise in changing the geomorphology of the coastline and seabed features.

التصویر المساحى الفوتوغرافی التحتمائى (الفوتوجرامترى): نموذج رقمى ثلاثى الأبعاد لدراسة الموقع الأثری المغمور تحت الماء لفنار الإسکندریة القدیم بجوار قلعة قایتباى.

يعد التصوير المساحى الفوتوغرافي التحتمائى (الفوتوجراميترى) احد التقنيات الجديدة في مجال الآثار الغارقة في مصر, حيث تم تطبيقه لأول مرة على الموقع الأثري المغمور تحت الماء والمعروف باسم موقع فنار الإسکندرية القديم الذى کان يقع على الطرف الشرقي لجزيرة فاروس القديمة بجوار قلعة قايتباي من الجهة الشرقية على عمق يتراوح بين 2 إلى 9 أمتار. وفي عام 2009/2010، قام المرکز الفرنسى للدراسات السکندرية CEAlex بوضع برنامجا لجمع بيانات باستخدام تقنية المساحة التصويرية (الفوتوجراميترى) لعمل نموذج للقطع الأثرية المکسورة , کالأعمدة وبعض التماثيل , ومحاولة اعادة تجميعها باستخدام الواقع الافتراضي فى شکل نموذج رقمى ثلاثي الأبعاد. ولکن في عام 2013 وبداية عام 2014 ، وبدعم من مؤسسة هونور فروست Honor Frost Foundation، تم تطوير وتحسين الأساليب المستخدمة فى التوثيق الفوتوجراميترى التحتمائى للحصول على صورة فوتوغرافية متکاملة للموقع المغمورتحت الماء بجوار قلعة قايتباي بالمجهودات اليدوية البسيطة وذلک باستخدام کاميرا DSLR وبعض المواد والأدوات البسيطة ومنخفضة التکلفة للحصول على نموذج رقمي ثلاثى الأبعاد لموقع الفنار المغمور، وأيضا لعمل نماذج ثلاثية الأبعاد لبعض القطع الأثرية، مثل التماثيل، وقواعد التماثيل وکذلک بعض العناصر المعمارية. نقدم في هذه الورقة البحثية أهمية طرق التصوير التحتمائى فى مجال الآثار الغارقة ثم کيفية معالجة البيانات من أجل إنشاء نموذج رقمى ثلاثى الأبعاد للموقع المغمور لفنار الإسکندرية القديم . حيث ان هذا التوثيق يعد مرحلة مهمة ومتقدمة فى دراسة الموقع الأثرى. حتى عام 2016 قد تم تصوير حوالي 7200 متر مربع فقط من مساحة الموقع المغمور ، والذي يتجاوزمساحته أکثر من 13000 متر مربع. Underwater photogrammetry: 3D Model for studying the submerged archaeological site of the ancient lighthouse of Alexandria near Qaitbay fort Abstract: Underwater photogrammetry is completely a new experience in underwater archaeology in Egypt, applied for the first time on the submerged archaeological site of the lighthouse of Alexandria situated on the eastern extremity of the ancient island of Pharos at the foot of Qaitbay Fort on a depth of 2 to 9 meters. In 2009/2010, the CEAlex launched a 3D photogrammetry data-gathering programme for the virtual reassembly of broken artefacts like columns and some statues, But In 2013 and the beginning of 2014, with the support of the Honor Frost Foundation, methods were developed and refined to acquire manual photographic data of the entire underwater site of Qaitbay using a DSLR camera, simple and low cost materials to obtain a digital surface model (DSM) of the submerged site of the lighthouse, and also to create 3D models of the objects themselves, such as statues, bases of statues and architectural elements. In this paper we present the methodology used for underwater data acquisition, data processing and modelling in order to generate a DSM of the submerged site of Alexandria’s ancient lighthouse. Until 2016, only about 7200 m2 of the submerged site, which exceeds more than 13000 m2, was covered

Understanding Diver Behavior on Underwater Cultural Heritage: Enriching the Observation Record Using Video Methods

Successful underwater heritage management requires a sound understanding of visitor behavior. Primary visitors to underwater heritage sites are divers whose behavior can pose risks to the integrity of site cultural heritage and tourism values. This study seeks to understand wreck diver in-water behavior. Conventional observation of diver behavior is limiting. Wearable cameras are becoming popular across many recreational activities and potentially expand the scope and quality of diver observation. Video observation is rarely used in such research. This article demonstrates the potential of video observation, describing the analysis of first-person video records to explore details of diver behavior on shipwrecks. The evidence demonstrates that while most divers behaved responsibly, a few contributed to most contact behaviors. The analysis details this behavior, identifying, for example, that deliberate holding and touching comprised most contacts. Such findings on diver behavior inform heritage and tourism management decisions and provide a baseline for future studies. Methodologically, the study demonstrates the power of this method of observing divers and other recreationists. This is particularly valuable for researching recreationalists in confined spaces, such as caves or shipwrecks. The quality of results allows for further evidence-based examination of motivations, values, intentions and meanings underlying observed diver behavior.

Underwater Excavation Records Using Underwater Acoustic Survey: A Case Study in South Korea

The most effective method for surveying underwater archeological sites is visually identifying areas with relics or remains through diving surveys. However, during underwater excavations, it is difficult to obtain images in turbid water. Furthermore, on-site diving is costly and time-consuming. Marine acoustic geophysical survey equipment is not significantly affected by underwater turbidity, and underwater excavations often rely on geophysical equipment for surface inspections. This study aimed to improve existing underwater excavation imaging through the application of acoustic survey methods. Underwater surveys were conducted via acoustic marine geophysical survey devices at three historically significant underwater sites in South Korea: Dangampo, Nakwoldo Island, and the Battle of Myeongnyang. At the Dangampo site, surveys were conducted using three different sonar devices—side scan sonar, multibeam echo sounder, and scanning sonar—and the results were compared; scanning sonar was the most effective. The methodology was further refined during excavations at the Nakwoldo and Myeongnyang sites. Results show that the scanning sonar can produce images that are more accurate than on-site drawings produced during underwater excavations, even in turbid underwater environments. Moreover, applied in conjunction with high-frequency geophysical exploration techniques, scanning sonar can significantly increase the reliability of investigations of buried underwater remains and relics.

Making the Invisible Visible: Underwater Malta—A Virtual Museum for Submerged Cultural Heritage

The seabed can be considered as the world’s largest museum, and underwater sites explored and studied so far provide priceless information on human interaction with the sea. In recognition of the importance of this cultural resource, UNESCO, in its 2001 Convention on the Protection of the Underwater Cultural Heritage, determined that objects/sites should be preserved in situ, whilst also advocating for public access and sharing. The implementation of these principles is not without difficulties. Some states have opened up underwater sites to the public—mainly through diving, yet the vast majority of the world’s population does not dive. In Malta, 7000 years of human occupation is reflected in and on the landscape, and recent offshore surveys show that the islands’ long and complex history has also left an indelible mark on the seabed. Besides difficulties related to their protection and management, these sites also present a challenge with regard to sharing and communicating. Recent advances in underwater imaging and processing software have accelerated the development of 3D photogrammetry of submerged sites and the idea for a virtual museum was born. The virtual museum, UnderwaterMalta, was created out of a need to share the plethora of underwater sites located on the seabed of the Maltese Islands. A multitude of digital tools are used to share and communicate these sites, offering visitors a dry dive into submerged sites that would otherwise remain invisible to the vast majority of the public. This paper discusses the basic principle of the sharing of underwater cultural heritage and the difficulties that beset the implementation of such a principle. A detailed explanation and evaluation of the methods used to gather the raw data needed is set in the context of the particular and unique working conditions related to deep water sites. The workings of this paper are based on first-hand experiences garnered through the recording of numerous wrecks over the years and the creation and launch of The Virtual Museum-Underwater Malta—a comprehensive virtual museum specifically built for “displaying” underwater archaeological sites that are otherwise invisible to the general public.

Graphene Oxide/Silver Nanocomposites as Antifouling Coating on Sensor Housing Materials

These days, sensors are widely used in a variety of underwater sites like marine monitoring, fish-farming and water quality monitoring. However, to achieve reliable sensor data from long-term monitoring in aqueous solution, several challenges still need to be solved. Biofilm formation both on sensor housings and membranes is among one of the most serious challenges, which strongly influences the sensor responds and the validity of the results. To prevent biofilm growth, a series of graphene oxide (GO)/silver nanoparticles (Ag NPs) nanocomposites (GOA) have been developed and coated on sensor housing materials, e.g. polypropylene. The antifouling property of the GOA nanocomposite has been demonstrated by antifouling tests using Halomonas. Pacifica (Baumann et al.) Dobson and Franzmann (ATCC® 27122) (H. Pacifica) and a mixture of marine algae. The antifouling property of GOA composites has been proved to be closely related to the dispersibility of Ag NP. The overall work might provide valuable insight into developing antifouling materials for sensors in general.

Flaking stone activity in the tradition of iron smelting from the 8th to 17th centuries AD in the Matano region, South Sulawesi, Indonesia

Lake Matano includes a complex of sites related to an iron-smelting industry that developed at the northeast tip of South Sulawesi between the 8th and 17th centuries AD. The sites include recently discovered underwater sites which possibly submerged because of an earthquake that had occurred in the region. An interesting finding at each site is the presence of flaked artifacts from chert. This raises the question of what was the role of flaked chert in the local tradition of iron smelting. The present study was conducted by combining ethnographic data from Lake Matano and analysis of chert artifacts excavated from the Rahumpu’u lakeshore site. The results show that chert artifacts were used as strike-a-lights and in particular for the combustion of fuel for iron smelting. Flaking chert was one of the skills possessed by the Matano indigenous iron smelters in utilizing the resources in their environment to produce a high quality of iron.

A Find of Transoceanic Pottery at Bwejuu Island of the Rufiji Delta and Mafia Island, Tanzania: More Clue to the Elusive Ancient Azania’s Metropolis of Rhapta

The island of Bwejuu is one of the islands of the Mafia archipelago on the central coast of Tanzania. It is only 15 km off the Rufiji Delta and its inhabitants carry out cultivation activities on the delta. The Rufiji delta has been considered by several scholars to be the location of the elusive ancient Azania’s metropolis of Rhapta. Past research on the island established that it was of the 16th–18th centuries post-Swahili civilization. This research has verified that finding although underwater work on the south-east part discovered pottery attributed to ancient transoceanic activities, possibly arriving from either the Mediterranean region or probably Oman or Indian regions. Sites with trade remains from those regions have been discovered on the Delta and Mafia archipelago. Also, an underwater site with wall-like structures believed to be remains of a long-submerged ancient settlement has recently been found in the northwestern waters of Mafia Island. The site has drawn attention of some archaeologists who believe it could be the long-lost metropolis of Rhapta. The new findings from Bwejuu Island may suggest that there are several trading sites in the region of the Mafia archipelago and the Rufiji Delta as outskirts of a large settlement which could be Rhapta. This study collected data through archaeological surveys and test excavations. Data analysis involved pottery attribute analysis and metric dating by thermoluminescence method.

Recently Discovered Iron Anchors from Tamil Nadu, East Coast of India

In maritime archaeological studies, anchors made of stone, wood, or metal have played a significant role in shipping, not only acted as a proxy during the period of their use but also suggesting maritime connections with other countries. Anchors of different types have discovered all over the world which used in the vessels engaged in carrying cargo, passengers as well as warships. Iron anchors were introduced in India by the European rulers, and later on, were manufactured in different parts of India. Like the stone anchors, different types of iron anchors have been recorded during onshore explorations as well as underwater sites with and without shipwreck remain along the Indian coast. In recent past, coastal explorations along Tamil Nadu coast brought to light two iron anchors at Tuticorin harbour while other two anchors displayed at the Government Museum, Egmore, Chennai. Both the iron anchors of Tuticorin harbour belong to Trotman type. In contrast, the iron anchors of the Government Museum, Egmore, belong to Old plan Long shanked Anchor (Admiralty Long Shanked) and Admiralty pattern anchor. This paper details a comprehensive study of these iron anchors and a comparative survey of the iron anchors of Tamil Nadu as well as India.