Underwater Archaeological Sites Research Articles

Application of the State-Of-The Art Engineering Methods in Nautical Archaeology

Modern interdisciplinary projects are connecting researchers from seemingly unrelated fields, like naval engineering and archaeology. However, archaeological remnants of the present days, such as ancient ships and ceramic transport containers, were created by engineers and artisans of the past. It is therefore meaningful to consider their function and construction from an engineering point of view, complementing the archaeological research. One track of the interdisciplinary project Archaeology of Adriatic Shipbuilding and Seafaring (AdriaS), founded by the Croatian Science Foundation, aims at better understanding of structural behaviour of the ancient seaborne structures, made of wood and ceramics. In addition, a reverse engineering method is considered in the analysis of underwater archaeological sites, by the simulation of capsizing of ancient ship. This paper presents the possibilities and limitation of the application of the state-of-the-art engineering methods in nautical archaeology. It focuses on the analysis of wooden and ceramics structures, particularly through the identification of open questions, and exploitation of proper material models. Moreover, it presents the complex fluid-structure interaction analysis of a ship capsizing event as a possible engineering tool for testing hypothesis.

Underwater photogrammetric monitoring techniques for mid-depth shipwrecks

Abstract Over the last few years there have been advances in technical diving, which have made it more accessible (including financially), making it possible to dive to greater depths and, consequently, reach underwater archaeological sites in deeper waters, which were previously considered “untouchable”. As these sites are now at potential risk of anthropic interference, new approaches to monitoring techniques are therefore considered necessary to ensure the protection of Underwater Cultural Heritage. This paper presents a protocol for monitoring techniques to be applied to ‘mid-depth archaeological remains’. The proposed technique is based on a combination of low-cost photogrammetric methods. Using as a case study a Roman era shipwreck from Majorca, off the east coast of Spain, this paper presents an ideal protocol for the essential first stages in protecting and managing the archaeological record of an underwater site at medium depth. The process gives immediate results, using photogrammetric and orthophoto coverage of the site to build up a highly accurate site map, as well as recording high-definition images in order to create a computer model of the site.

Sea-level rise and archaeological site destruction: An example from the southeastern United States using DINAA (Digital Index of North American Archaeology).

The impact of changing climate on terrestrial and underwater archaeological sites, historic buildings, and cultural landscapes can be examined through quantitatively-based analyses encompassing large data samples and broad geographic and temporal scales. The Digital Index of North American Archaeology (DINAA) is a multi-institutional collaboration that allows researchers online access to linked heritage data from multiple sources and data sets. The effects of sea-level rise and concomitant human population relocation is examined using a sample from nine states encompassing much of the Gulf and Atlantic coasts of the southeastern United States. A 1 m rise in sea-level will result in the loss of over >13,000 recorded historic and prehistoric archaeological sites, as well as over 1000 locations currently eligible for inclusion on the National Register of Historic Places (NRHP), encompassing archaeological sites, standing structures, and other cultural properties. These numbers increase substantially with each additional 1 m rise in sea level, with >32,000 archaeological sites and >2400 NRHP properties lost should a 5 m rise occur. Many more unrecorded archaeological and historic sites will also be lost as large areas of the landscape are flooded. The displacement of millions of people due to rising seas will cause additional impacts where these populations resettle. Sea level rise will thus result in the loss of much of the record of human habitation of the coastal margin in the Southeast within the next one to two centuries, and the numbers indicate the magnitude of the impact on the archaeological record globally. Construction of large linked data sets is essential to developing procedures for sampling, triage, and mitigation of these impacts.

3D survey and modelling of shipwrecks in different underwater environments

Abstract Experiments carried out by a combined team of the Ca’ Foscari and IUAV Universities of Venice, on ancient shipwrecks with different characteristics in different environments (shallow water cargoes of marble stones and a deep water mound of amphoras), confirm the potential of three-dimensional surveys in documenting underwater archaeological sites. Multi-image photogrammetry is the principal and innovative technique used, but we have confirmed the necessity of accompanying this new system with a precise topographical net. This last aspect is particularly evident when it is necessary to solve the problem of the documentation of a multi-strata mound of amphoras, anchoring 3D models of each stratum as it is removed. Photogrammetric models must be processed with 3D software modelling to interpret the textured meshes and to construct polygonal models, selecting the important aspects of the objects, and eliminating the ‘noise’ of the point cloud. The 3D model can easily be used to reconstruct the original arrangement of the cargo, on which it is then possible to make various calculations and considerations of nautical engineering.

A multivariate approach to the study of orichalcum ingots from the underwater Gela's archaeological site

In this work a careful ICP-OES and ICP-MS investigation of 38 ancient ingots has been performed to determine both major components and trace elements content to find a correlation between the observed different features and the composition.The ingots, recovered in an underwater archaeological site of various finds near Gela (CL, Italy), were previously investigated by X-Ray Fluorescence (XRF) spectroscopy to know the composition of the alloy and it was found that the major elements were copper and zinc, in a ratio compatible with the famous orichalcum similar to the contemporary brass that was considered a precious metal in ancient times. The discovery of huge amount this alloy is extraordinary.Following a chemometric approach at first, the use of Principal Component Analysis (PCA) and Cluster Analysis (CA) allowed us to highlight three well-defined groups of ingots and to point out three ingots that appeared outlier with respect to the whole sample set. Linear Discriminant Analysis (LDA) and Soft Independent Modeling of Class Analogy (SIMCA) enabled us to confirm the difference between the hypothesized groups. The prediction power of the variables computed by SIMCA allowed us pointing out some elements able to differentiate each group.The three well-defined groups of ingots resulting from the chemometric analysis were in agreement with the observations of some morphological parameters such as ingot shape, width, and length and weight and by the presence of different kind of patina.The appearance of three distinctive families of ingots can indicate different geographical location of the furnace, different technology stages and/or different raw material used in melting process and the morphology is indicative of cast diverse technologies. These findings can signify the starting point for giving important insights in the archaeometric study of the orichalcum ingots regarding the provenience and the manufacture technologies.

Using Sector-Scan Sonar for the Survey and Management of Submerged Archaeological Sites

© 2017 The Authors. International Journal of Nautical Archaeology © 2017 The Nautical Archaeology Society. This article reports the results of using a sector-scan sonar to record diverse submerged archaeological sites in shallow and deep water. The Kongsberg MS1000 sector-scan sonar was developed for commercial applications, typically underwater inspections of bridges, dams, ports and harbours. The ability of the device to rapidly generate high-quality, geometrically accurate scans of submerged features, coupled with its ease of use and deployment make it a potentially important, yet largely overlooked, tool for survey and management of underwater archaeological sites. As one of several technologies available, the paper examines its advantages and limitations, and considers, through case studies, under which conditions it is most effectively deployed.

The Conservation Research Laboratory and Conservation of Artifacts from the Mardi Gras Shipwreck Project

Conservation of artifacts from underwater archaeological sites is vital, and the role of the Conservation Research Laboratory (CRL) is to ensure the artifacts’ long-term stabilization. Conservation serves several purposes, not the least of which is protecting the tangible remnants of a particular site. These artifacts aid in identification of the site, provide details of the activities of the people inhabiting the site, and also provide the archaeologist, and ultimately the public, with a connection between the past and the present.

Biodeterioration of marble in an underwater environment

This study examines the deterioration of geomaterials used throughout history that today may be found lying on the ocean floor. Submerged archaeological sites including cargoes from shipwrecks or ancient city ruins have been a topic of interest from a perspective of in situ musealization, as a way of making underwater cultural heritage accessible to the public. In an experimental study conducted at an underwater archaeological site in the Bay of Cádiz (SW Spain), we subjected two types of marble (Carrara and Macael) to three conditions to which submerged archaeological objects are often exposed: full exposure to the water column, natural processes of burial and unearthing, or permanent burial. After an 18-month study period, the factor found to mostly affect these materials was their biological colonization. This factor was assessed by estimating total surface biocover and the rate of surface biocolonization, and also through the identification of skeletons and associated alteration forms by light microscopy, and scanning electron microscopy (SEM). Biofouling and bioerosion were the main causes of biodeterioration and dependent on the position of the marble specimens in the seawater. The response of both materials was similar, though dolomite crystals in the Carrara marble acted as a protective barrier against actively penetrating microorganisms. These investigations have allowed the study of tracers left by epilithic encrusting organisms and endolithic bioeroders on marbles intentionally exposed to seawater, providing new insights to the understanding of the biodeterioration processes occurring in cultural heritage stones, with significant implications when they are part of underwater archaeological remains.

Virtual dives into the underwater archaeological treasures of South Italy

The paper presents a virtual diving system based on a virtual reality (VR) application for the exploitation of the Underwater Cultural Heritage. The virtual diving experience has been designed to entertain users, but its added pedagogical value is explicitly emphasized too. In fact, the ludic activities, consisting in the simulation of a real diving session from the point of view of a scuba diver, are following a storyline described by a virtual diving companion who guides users during the exploration of the underwater archaeological site. The virtual diving system provides general and historical-cultural contents, but also information about the flora and fauna of the specific submerged site to the users. The results collected through user studies demonstrate that the proposed VR system is able to provide a playful learning experience, with a high emotional impact, and it has been well appreciated by a large variety of audiences, even by younger and inexperienced users.

The impact of 5 years’ underwater exposure in the Baltic Sea (Puck Bay) on selected properties of English oak wood samples

In order to understand the influence of the underwater marine environment on changes in selected properties of contemporary wood, samples of oak wood were tested following several years of exposure at an underwater archaeological site (Puck Bay, Baltic Sea). The content of the major and minor components of the wood, as well as the total amount of minerals were determined. Selected physical properties were tested, as well as the strength and resistance of marine wood to rot caused by Basidiomycetes fungi. The study showed a decrease in the strength of the wood, changes in the chemical composition, and an increase in the quantity of mineral substances. In addition, a marked increase was found in the susceptibility of the tested wood to degradation by Basidiomycetes. These results indicate that the immersion of oak wood in the waters of Puck Bay caused significant changes in its physical, chemical and biological properties. Observations of changes occurring in contemporary wood can be useful in the monitoring of underwater archaeological sites.

3D MODELLING AND MAPPING FOR VIRTUAL EXPLORATION OF UNDERWATER ARCHAEOLOGY ASSETS

Abstract. This paper investigates immersive technologies to increase exploration time in an underwater archaeological site, both for the public, as well as, for researchers and scholars. Focus is on the Mazotos shipwreck site in Cyprus, which is located 44 meters underwater. The aim of this work is two-fold: (a) realistic modelling and mapping of the site and (b) an immersive virtual reality visit. For 3D modelling and mapping optical data were used. The underwater exploration is composed of a variety of sea elements including: plants, fish, stones, and artefacts, which are randomly positioned. Users can experience an immersive virtual underwater visit in Mazotos shipwreck site and get some information about the shipwreck and its contents for raising their archaeological knowledge and cultural awareness.

SURVEYING THE UNDERWATER ARCAHEOLOGICAL SITE OF CAPE GLAROS AT PAGASETIKOS GULF

Abstract. The Hellenic Institute of Marine Archaeology (H.I.M.A.)1 has been conducting an underwater archaeological research in the west coast of southern Pagasetikos Gulf, since 2000. Every year the underwater research focuses on specific archaeological targets that have been recovered during previous field campaigns. The current publication elaborates on the comprehensive documentation of the underwater archaeological site at Cape Glaros, during the 2015 field season, under the direction of the archaeologist Elias Spondylis. The 2015 research campaign was conducted within the framework of the ITACA- Innovation Technologies and Applications for Coastal Archaeological sites European Project (FP7/2007-2013, GA No 606805), at two archaeological sites, namely the Cape Glaros and Metohi. It was among the most important challenges of the project to successfully produce the detailed and accurate 3D mapping of the Cape Glaros site that covers an extended area. Four large concentrations of pottery finds and numerous anchors of different typology have been recorded, that can be dated from the late Hellenistic to the Byzantine periods. This challenge was tackled through the simultaneous implementation of three recording methods; photogrammetry, geodesy and conventional architectural mapping. The workflow of the documentation process, including data acquisition, processing and graphic visualization, along with the derived results are presented below. 1The Hellenic Institute of Marine Archaeology (H.I.M.A.) is a private, non-profit organization, founded in 1973, which undertakes maritime archaeological research under the supervision or in collaboration with the Greek Ministry of Culture. It has over 100 members, with diverse academic credentials, all of whom work, mainly, on a voluntary basis. 3D recording of underwater archaeological sites has been applied to numerous projects that have been carried out by the multidisciplinary team of H.I.M.A. in locations of utmost archaeological importance and interest, such as Modi island (Poros) and numerous wreck sites in Pagasetikos and South Euboean (Diamanti, Vlachaki, 2015) Gulfs and others.

VIRTUAL DIVING IN THE UNDERWATER ARCHAEOLOGICAL SITE OF CALA MINNOLA

Abstract. The paper presents the application of the technologies and methods defined in the VISAS project for the case study of the underwater archaeological site of Cala Minnola located in the island of Levanzo, in the archipelago of the Aegadian Islands (Sicily, Italy). The VISAS project (http://visas-project.eu) aims to improve the responsible and sustainable exploitation of the Underwater Cultural Heritage by means the development of new methods and technologies including an innovative virtual tour of the submerged archaeological sites. In particular, the paper describes the 3D reconstruction of the underwater archaeological site of Cala Minnola and focus on the development of the virtual scene for its visualization and exploitation. The virtual dive of the underwater archaeological site allows users to live a recreational and educational experience by receiving historical, archaeological and biological information about the submerged exhibits, the flora and fauna of the place.

Chemical signatures of ancient activities at Chan b'i - A submerged Maya salt works, Belize

Chemical analysis was undertaken at Chan b'i, an Early Classic (300–600CE) ancient Maya submerged salt works to find activity areas not apparent from artifactual materials recovered from excavations. Chan b'i is one of 105 salt works located underwater in Paynes Creek National Park, Belize where wooden buildings are preserved due to mangrove peat matrix. The acidic peat (pH6) preserved wood and other botanical remains, but is not conducive to the preservation of bone. Consequently, the artifactual record may be biased against the preservation of animal food remains and human burials, which are typically found at Maya settlements. In this study, we use inductively coupled plasma-mass spectroscopy (ICP-MS) to evaluate if there is evidence of other activities in addition to the salt production. The present study extends soil chemistry research to underwater archaeological sites. The results of chemical patterns indicate activity locations inside and outside of wooden architecture not shown by the artifactual remains.

Design and testing of an innovative cleaning tool for underwater applications

The aim of this work is to describe the development of an innovative cleaning tool for underwater applications, to be used in particular in the field of underwater archaeology. This work takes place in the framework of the EU FP7–funded ARROWS project. ARROWS adapts and develops low-cost autonomous underwater vehicle technologies to significantly reduce the costs of underwater archaeological operations, covering the full extent of archaeological campaigns. The project deals with underwater mapping, diagnosis and cleaning tasks. During the first half of the project, a cleaning tool prototype, able to be mounted on underwater vehicles, has been worked out: this cleaning tool will be exploited not only during research missions but also for the periodic monitoring, controlling and maintenance activities of well-known underwater archaeological sites (e.g. periodic cleaning operations).

Newly Discovered Marks of Dwelling in Lake Sāviena (Latvia)

In 2014 and 2015, new underwater archaeological sites were discovered in Lake Sāviena in the east of Latvia. The first site, according to C14 dating, goes back 4510 +/-55 years. In the other site, artefacts and ceramics from the Late Iron Age were discovered. Here, on the shore of the lake, adjacent cultural occupation of the settlement was discovered. It is possible to make preliminary conclusions that the shores of Lake Sāviena had been inhabited for a long time, which was certainly associated with the lake’s waters. Key words: lake dwelling, flying lake, underwater constructions, settlement. DOI: http://dx.doi.org/10.15181/ab.v23i0.1307

High-Resolution Underwater Robotic Vision-Based Mapping and Three-Dimensional Reconstruction for Archaeology

Documenting underwater archaeological sites is an extremely challenging problem. Sites covering large areas are particularly daunting for traditional techniques. In this paper, we present a novel approach to this problem using both an autonomous underwater vehicle (AUV) and a diver-controlled stereo imaging platform to document the submerged Bronze Age city at Pavlopetri, Greece. The result is a three-dimensional (3D) reconstruction covering 26,600 m2 at a resolution of 2 mm/pixel, the largest-scale underwater optical 3D map, at such a resolution, in the world to date. We discuss the advances necessary to achieve this result, including i) an approach to color correct large numbers of images at varying altitudes and over varying bottom types; ii) a large-scale bundle adjustment framework that is capable of handling upward of 400,000 stereo images; and iii) a novel approach to the registration and rapid documentation of an underwater excavations area that can quickly produce maps of site change. We present visual and quantitative comparisons to the authors' previous underwater mapping approaches.

Studying the Cannons of Punta Santa Anna, Spain: In Situ Conservation, Promoting Public Access, and Monitoring Iron Corrosion

The 2001 UNESCO convention for the Protection of Underwater Cultural Heritage (UCH) encourages and supports projects that would make accessible to the general public underwater cultural sites. Since 2010 the Catalonian Federation of the World Underwater Federation (FECDAS), have been developing outreach activities with the objective of promoting the protection of the UCH among recreational scuba divers. The purpose of this paper is to introduce one such project, the Punta Santa Anna in Blanes, Spain. This project has three objectives: the promotion of UCH to the general public, the in situ protection of this underwater archaeological site, and a case study on iron corrosion processes. FECDAS/CMAS will create an underwater archaeological park where recreational scuba divers will be able to visit some purposely selected archaeological iron cannons. To expose UCH to the general public will potentially affect the integrity of these artefacts. This risks potential damage and so, with the objective of minimizing potential threats, a series of protective measures and a systematic monitoring programme have been planned. The programme is designed to study the relationship between the underwater environment and the artefacts. The aim is to acquire a better understanding of the corrosion processes of iron objects present in marine underwater sites.

Project VISAS: Virtual and Augmented Exploitation of Submerged Archaeological Sites‐Overview and First Results

AbstractVISAS (Virtual and Augmented Exploitation of Submerged Archaeological Sites) is a collaborative research project created to improve the responsible and sustainable exploitation of underwater archaeological sites. This strategic goal is reached through the development of three services. The first concerns the 3-D reconstruction of the underwater environment by using a methodology for optical and acoustic bathymetric data fusion. The second is based on a virtual reality system for dive session planning and 3-D exploration of the underwater site. Finally, the third service is intended to enrich the diving experience through a virtual guide running on an underwater tablet equipped with a hybrid tracking system. This paper provides a summary report of the project and an overview of the partial results achieved.

The CoMAS Project: New Materials and Tools for Improving the In situ Documentation, Restoration, and Conservation of Underwater Archaeological Remains

AbstractOn November 2, 2001, the UNESCO Convention on the Protection of the Underwater Cultural Heritage provided a detailed state cooperation system and set out the basic principles for the protection of underwater cultural heritage. To date, the Convention has been ratified by 51 countries. One of the four main principles states that the In situ preservation of underwater cultural heritage should be considered as the first option before allowing or engaging in any further activities. In accordance with these principles and recommendations, in the last years many projects intended for developing and testing new techniques and tools to support In situ conservation of underwater archaeological remains have been funded and are now underway.This paper describes the contribution of the CoMAS project (In situ conservation planning of Underwater Archaeological Artifacts—<ext-link ext-link-type="uri" href="http://www.comasproject.eu">http://www.comasproject.eu</ext-link>), funded by the Italian Ministry of Education, Universities and Research (MIUR) and run by a partnership of private companies and public research centers. The CoMAS project aims at the development of new materials, techniques, and tools for the documentation, conservation, and restoration of underwater archaeological sites in their natural environment. The paper describes in detail the results achieved during the project in the development of innovative materials, mechatronic tools, and armed remotely operated vehicle systems that can efficiently support the restorers' work in all their activities for preserving underwater cultural heritage in its original location on the seafloor.