Submerged Landscapes

"The Arabian Gulf is a fairly shallow sea and during the Last Glacial Maximum was an open landscape that may have formed a refugia for human groups. The discovery of archaeological remains predating 8,000 years ago in the marine areas of the North Sea and English Channel would suggest that the Arabian Gulf also has a similar potential for the favorable survival of pre-marine transgression deposits. In addition, The Gulf has been part of a maritime trade network which extends back into the 7th millennium and so the region has the potential for shipwrecks from both the historic and prehistoric periods. However, despite this very little maritime archaeological research directed towards the discovery of such remains has been undertaken. Given the expense and logistical issues associated with diving and underwater survey this may not be entirely surprising. To survey the marine areas of Qatar alone using a team of divers would take many years, particularly given strong regional currents and limited visibility. In recent years the rapid development of geophysics has provided new opportunities to investigate wider areas of the marine landscape and to develop strategies for targeted diver inspections of geophysical anomalies.

The analysis of a large tract of geophysical data off the northwest coast of Qatar revealed more than 80 anomalies with a sea bed expression, some of which were clearly modern, and others that were considered to have reasonable archaeological potential. Of the anomalies subject to subsequent diver inspection, none proved to be of archaeological interest. However, the visual inspection of geophysical anomalies is providing valuable regional baseline data for the interpretation of anthropogenic marine signatures. The clarification of signatures from different types of anomalies enables the calibration of regionally important geophysical data. In addition, these inspections have significantly increased our understanding of the seabed characteristics around Northeastern Qatar. Future geophysical survey will be focused not simply on anomalies but on characterising the submerged landscape using higher resolution geophysical data from a range of sensors.
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Since the first peopling of Australia and New Guinea (the continent of Sahul) during times of lower sea level more than 60,000 years ago, approximately 2 million km of land, roughly one-third of the present continental land mass, has been drowned by sea-level rise. Landscapes encountered and settled by thousands of generations of people through out the continent have been inundated by rising seas as polar ice and glaciers melted into the world's oceans. While some archaeological sites formed within these landscapes were no doubt destroyed by the rising seas, many sites are likely to have survived. This sub merged archaeological record represents the majority of human occupation in Sahul, spanning the period from initial peopling of the continent to 7000 years BP. As a major frontier in Australian archaeology, investigation of what is now seabed will ultimately lead to revised and enhanced understanding of the continental archaeological record. By reevaluating the coastal zone, submerged landscapes, and continental shelf, considera tion for these past cultural landscapes in what is now Sea Country has the potential to profoundly reshape the archaeological discourse of Australia and New Guinea.

This volume gathers papers presented at the Maritime Archaeology Graduate Symposium, held in Oxford in 2018. The event was an Honor Frost Foundation initiative dedicated to new and upcoming research focused on eastern Mediterranean Archaeology and realised by a committee from the Centre for Maritime Archaeology, University of Southampton, and the Oxford Centre for Maritime Archaeology, University of Oxford. These essays represent the proceedings of this conference and contain some of the latest research and fieldwork in the Mediterranean and beyond. Topics include ships, ports and port systems, maritime economics, chemical analysis of archaeological remains and legislation in
maritime archaeology. This publication is the product of an endeavour to promote early career research for maritime archaeologists with unique foci, and to establish a platform for them to discuss their findings with the wider community.

With an introduction by Lucy Blue and Naseem Raad.

Geoarcheological surveys undertaken over the past two decades at Gray's Reef National Marine Sanctuary, 32 km offshore Georgia, and nearby JY Reef have recovered archeological and paleontological materials dating from the Late Pleistocene, primarily Marine Isotope Stage (MIS) 3, 59–24 KYBP as well as the early-to-mid Holocene, 6000 BP. The paleontological materials include both invertebrate and vertebrate taxa from both the Pleistocene and Holocene while the archeological materials are Holocene age. Sediment coring has developed a more comprehensive picture of the inner-to-mid continental shelf sediment prism of the Georgia Bight. Optical petrography, scanning electron microscopy, electron dispersive spectroscopy (SEM-EDS) and wavelength dispersive X-ray diffraction (XRD) have been used to characterize Gray's Reef lithic artifacts and nearby outcrops which are both primarily Pliocene age calcareous sandstones. JY Reef is, by contrast, a coquina rich in fossil and subfossil materials but depauperate in any archeologic finds. Petrologic and geochemical data have been developed for both the outcrops and artifacts that are in good agreement with previous studies using optical petrography.

The North Sea bed hosts remains of Pleistocene and Early Holocene landscapes that were, mostly gradually, inundated following the last deglaciation. Archaeological remains fromthe seabed obtained by fishing, dredging, and sand suppletion include human skeletal remains. Radiocarbon dating reveals that most of these are Mesolithic although a few Late Palaeolithic and historic remains are represented. Samples with known stable isotope ratios δ13C andδ15N show that Mesolithic inhabitants of ‘Doggerland’ had a significant component of freshwater fish in their diet. Thismeans the 14C dates are subject to a reservoir effect mainly determined by the freshwater bodies at the time. Because of the lack of context, the magnitude of the reservoir effect cannot be derived, so that the 14C dates cannot be precisely calibrated to absolute ages. However, a distinct correlation is observed between the δ15N values and the (uncalibrated) 14C dates, suggesting a chronological development.

In December 2011 the Qatar National Historic Environment Record (QNHER), Qatar Museum Authority and University of Birmingham, collaborated with Texas A & M University – Qatar (TAMUQ) to visualize sea level change and its effects on patterns of human occupation on a site specific level.  This data was derived from extensive coring and subsurface modeling in Wādī debayān, north western Qatar.  During prehistory the wadi would have been subject to dynamic periods of environmental change.  This has been related to two periods of dramatic sea-level rise during the Holocene geological epoch (12000BP to the present era).  Evidence from other sites in Qatar indicate that these two episodes may have reached ‘highstands’ of between 1 and 3m above modern sea level. 

Vizualising the prehistoric environment of the wadi presents an important opportunity to test several of our assumptions about these past environments in the wadi and contribute to ongoing research aims. Immersive visualization allows the examination the dramatic effects dynamic environmental change would have had upon past populations and prehistoric environments in the Arabian Gulf. This tool not only has applications for academic based research but also for providing uncomplicated public access.  There are important benefits for schools, universities and museums, where visual representation can convey concepts more readily than descriptive narrative.

The submerged Mesolithic site at Bouldnor Cliff offers a unique glimpse into the rapidly changing coastal environment ca. 8000 BP. At a depth of only 11m in the Solent, wood artefacts and ecofacts have survived in an anoxic layer of peat overlaid with a clay stratum, and in association with several deposits of worked flints. Careful diving, excavation, and sampling protocols were followed to ensure that the fragile, waterlogged timbers were surfaced in the same condition as when they were deposited. The high level of wood preservation has made it possible to determine which of these timbers are ecofacts, forest detritus from the once-freshwater fen, and which are artefacts, timbers worked with stone tools at what may have been a logboat construction site. While many timbers are likely ecofacts representing the surrounding oak (Quercus sp.) dominated forest and others are of ambiguous categorization, a few are clearly artefacts. These include oak trunk fragments with apparent axe or adze hollowing marks, wood ‘cores’ with ‘chip’ debitage, axe marks on de-barked limbs, sharpened pegs, and an intriguing group of planks that were cut flat on one side and rounded on the other. As a whole, the assemblage is indicative of woodworking and timber conversion technologies not attested elsewhere in Britain until 2000 years later, if at all. The site also demonstrates the human responses to a changing coastline, one of which was addressing the needs for waterborne transit in an increasingly marshy environment that would soon succumb to the ingressive sea.

ABSTRACT Investigation of shallow-marine environments for submerged prehistoric archaeology can be hampered in many localities by extensive bedrock exposure and thus limited preservation potential. Using the concept of ‘seamless archaeology’ where land-based archaeology is integrated across the intertidal zone through to the offshore, a multi-disciplinary approach is essential. This approach taken in the Bay of Firth, Orkney uses geophysics, historical archive and ethno-archaeology, coastal geomorphology, palaeo-environmental analyses and sea-level science, and allows a clearer understanding of the landscape in which prehistoric settlers lived. While acknowledging the limitations of the preserved environment, we are successful in identifying areas of archaeological potential on the sea-bed for both upstanding structural elements as well as sediment preservation that contains evidence for human occupation. This has wider implications beyond Orkney's World Heritage sites to provide a blueprint for similar studies elsewhere in the coastal zone. © 2012 The Authors

In the light of the increasing industrial activity in the oceans, management of the submerged cultural heritage beyond the shallow zone is becoming a matter of increasing concern. National legislative bodies, together with the 2001 UNESCO Convention on the Protection of the Underwater Cultural Heritage, underline the need to develop a legal and methodological framework for management of the submerged cultural heritage. Besides ship wrecks, which are numerous, Stone Age settlements likely represent the dominant type of submerged cultural heritage sites requiring competent and cost-effective management. As the average sea level during successive glaciations was, for long periods, more than 100 m below that of today, and as the subsequently submerged areas appear to have been more intensely inhabited than hitherto imagined, it seems logical to expect well-preserved remains of early human settlement to be associated with these highly productive prehistoric coastal areas. The archaeological finds recorded demonstrate that this settlement, even in Northern Europe, extends back as far as 1 million years.

A pre-requisite for a successful implementation of future
legislative initiatives is the development of a technical basis
consisting of 1) cost-effective methodologies for mapping and
investigating the submerged Stone Age sites and 2) cost-effective
methods for investigating/excavating the deeper submerged
Stone Age sites.

This study addresses the latter point because it is seen as being important to facilitate an interactive development of legislation and the possibilities that technological advances in underwater acoustic sensing, positioning, robotics and mechatronics can provide. For example, it would presently be quite problematic to have to carry out an investigation of a well-preserved mammoth-hunter site covered by 5 m of sediments and located at a depth of 70 m. How should one excavate such a site at a reasonable quality level? It is likely that we may have to deal with situations of this type in the near future.

This paper discusses how the maximum amount of information can be obtained about such sites during a preexcavation evaluation stage by physical characterization of cultural and surrounding layers and sediment/dirt DNA analysis, etc, as well as the possibilities for on-site excavation or, alternatively, the extraction of blocks of sediment for excavation under controlled conditions during an actual investigation.