As little as ten years ago, the idea of producing a systematic and comprehensive examination of the glacial-maximum geomorphology and terrestrial environment of Europe's continental shelf at a pan-continental scale would have seemed either hopelessly fanciful or impossibly ambitious.
For archaeologists, the existence of a vast and now submerged prehistoric territory exposed at lowered sea level had barely entered the professional and academic consciousness. Traditionally, this underwater realm has been regarded as too inaccessible and difficult to deal with, and too ravaged by destructive processes to preserve more than a vestigial record of archaeological sites or landscape features, a record, moreover, considered unlikely to make any difference to the understanding of world prehistory. Such pioneering studies as exist have been focused mainly at local or national level, and sometimes at a regional level, for example in relation to particular sea basins such as the North Sea or the Baltic.
For earth scientists, more familiar with large-scale collaboration at a continental or global scale, the continental shelf has been extensively studied in the context of plate tectonics, the extension of continental geology under the sea, national resources, coastal zone management, the exploitation of minerals and hydrocarbons, cable and pipeline route surveys and, to a certain extent, Pleistocene Ice Age sea-level change. It has also been surveyed and mapped topographically at a resolution sufficient for safe navigation. However, analysis and interpretation of seabed data as evidence of a former terrestrial landscape that has been repeatedly exposed and then submerged by sea-level change has remained somewhat peripheral to their concerns.
The idea that the techniques already developed and the large quantities of data obtained piece-meal for many different applications could by synthesized and interpreted to reconstruct and understand the prehistoric occupation of the continental shelf during the various phases of low sea level was not on anybody's agenda until very recently.
Such is the fate of research questions that fall outside the scope of pre-existing research agendas. Despite boldly expressed aspirations and much protestation of good faith about the virtue of ‘interdisciplinarity’, successful integration of ideas and methods drawn from many different disciplines remains a formidable challenge; by definition such endeavors lie at the boundaries between more established disciplines and are discounted in consequence, typically falling into the gaps between different conceptual structures, administrative organizations and funding bodies. In turn, the new ideas and agendas required to give momentum to the study of unfamiliar research questions are liable to slow and fitful development. The continental shelf, viewed as a submerged landscape and a former terrestrial environment, is no exception, and has long remained a marginal zone in both a literal and a conceptual sense.
An important recent spur to changing research agendas is the growing importance of understanding sea-level change in a world of climate warming and impending sea-level rise, and the threat this poses to human life and livelihoods on a global scale. The study of Quaternary ice caps, the crustal impact of redistributed masses of ice and water, and the changes of sea level on the continental shelf have been studied in several large global collaborations. But even here, difficulties in the efficient application of standard marine geophysical techniques, compounded by stratigraphic discontinuities and disturbances of seabed sediments, have hampered the study of submerged shoreline features, and more accessible proxy data has often been preferred such as deep-sea sediment cores, shoreline features above modern sea level, or the outputs of Earth-geophysical and climatic modeling. Yet, interpretations based on proxy data and theoretical modeling are only as good as the assumptions that underpin them, and in need of continuous testing and refinement against field data. Since sea level has been lower than present for most of human history on this Earth and in most regions, it follows that most of the relevant data of past shorelines is likely to be now submerged on the seabed. Moreover, sea-level change is only one part of the history of the continental shelf, being inextricably bound up with the geological history of the Earth's crust and the geomorphological transformations at its surface, as the chapters in this volume make clear.
It was precisely this challenge – the need to bring together a multi-national group of individuals with very different scientific and archaeological skills and interests, but a shared interest in the terrestrial environment of the continental shelf and its potential for the preservation of archaeological data relating to human settlements – that brought into being the idea of “Project Deukalion”, conceived in 2008 by Nic Flemming and Dimitris Sakellariou. This rapidly led to the formation of the Deukalion planning group with 16 experts from eight European countries and the goal of drafting the outlines of a multidisciplinary project.
The Deukalion initiative was subsequently expanded and incorporated into the SPLASHCOS network in 2009. SPLASHCOS (Submerged Prehistoric Archaeology and Landscapes of the Continental Shelf) is the outcome of a proposal to the EU COST (Cooperation in Science and Technology) program, designed to stimulate international and interdisciplinary collaboration. As COST Trans-Domain Action TD09020, SPLASHCOS provided sustained support and funding over a four-year period to bring together in regular meetings archaeologists, geoscientists, geophysicists, paleoclimatologists, oceanographers, sea-level experts and representatives of government organizations and offshore industries from 25 European States and over 100 research institutions and agencies in a concerted effort to develop a new research agenda. Funds also included encouragement and training of early-career researchers, and other dissemination activities (see www.splaschos.org for further details). The momentum created by that initiative continues.
This volume is the first major collaborative publication to result directly from the sustained activities of the SPLASHCOS initiative. It is in fact the first of a pair of volumes, each reflecting the outcome of the two Working Groups that formed the central pillars of the SPLASHCOS Action: Working Group 1, Archaeological Data and Interpretations, led by Anders Fischer; and Working Group 2, Environmental Data and Reconstructions, led by Jan Harff. In the event, we have assigned the results of Working Group 2 to Volume 1 in the series, both because that work has proceeded on a faster timetable, and because an understanding of the geological and palaeoenvironmental history of the continental shelf logically precedes an elaboration and evaluation of the archaeological remains recovered from the seabed. The second volume will follow and examine in detail the evidence of prehistoric archaeology.
In keeping with the nature and aspirations of the SPLASHCOS action, the authorship of this volume is collaborative, multi-national and multi-disciplinary, and the geographical scope pan-European, dealing with all the major European sea basins, ranging from the Atlantic Ocean and North Sea in the north-west, through the Baltic and the Mediterranean, to the Black Sea in the south-east.
The primary focus is the nature of the continental shelf as it would have existed during periods of lowered sea level as a terrestrial landscape – its variable geographical configuration, topography, sedimentary depositional processes, stratigraphy, climate, ice limits, river drainage, flora and fauna, and its potential and history as a zone of human habitation and a repository of archaeological data. Reconstructing these features is no simple matter, the biggest problem being the multiple ways in which successive cycles of sea-level rise and fall have variously buried, obscured, exposed, eroded or destroyed the material traces of past human activities and their original landscape setting. Hence, a major theme of research and interpretation must be the ways in which sub-sea processes, including commercial activities, have affected the preservation and visibility of formerly terrestrial deposits and their associated archaeological remains.
The problems posed by differential preservation and visibility are not insuperable, nor are they problems unique to the study of submerged land surfaces. Terrestrial archaeologists, too, have increasingly come to realize that the distribution of archaeological sites on land does not reflect in any simple way the distribution of past human activities or past human populations. Rather, such distributions represent a complex interaction between the locations where past peoples left the material traces of their existence, the nature of the activities carried out in these different locations, the manner in which material was discarded, and the various natural and human processes that acted subsequently to transform the land surface.
The term ‘landscape taphonomy’ is sometimes used to describe this field of research, referring to the variable ways in which the physical features of a past land surface, including land forms, soils and sediments, and the archaeological materials deposited on or in them by successive human generations, have been variously buried, exposed, preserved, mixed, scattered, destroyed or otherwise transformed, whether by processes that are natural in origin or anthropogenic. The problem is especially acute under water, but no less present on dry land. In both cases, the nature of these transformations remains poorly understood, under-researched, and in need of much greater attention.
The opening chapters of this volume provide comprehensive overviews at a continental scale of key themes such as geological structure, large-scale tectonic evolution, sea-level change, glacial history, climate, environment and mapping, including the vexed issue of bathymetric maps and databases; these are often assumed to exist already in adequately published or digital form but in reality they are mostly produced for quite different purposes and are too inaccurate or of too coarse a resolution to be of more than limited usefulness for archaeological and paleoenvironmental purposes. The existing accessible and published data provide a broad framework in many regions, but as with so many other examples in the history of science, new research questions will demand the collection of new and more detailed data with methods best adapted to yield the necessary information.
These opening chapters are not confined narrowly to the continental shelf but encompass the continental land mass more widely, and they make for illuminating reading relevant to everyone interested in the natural and human history of the European continent over the past one million years and more.
These themes are followed through in more detail in the sea-basin chapters, which also include reference to key underwater archaeological finds as examples of preservation mechanisms and the potential for future discoveries. A notable feature is the comprehensive listing of online sources of information. In a digital world, information is increasingly being made available on the internet, either as searchable, accessible and properly maintained databases, or in more ephemeral or inaccessible form, and this is likely to be a growing trend for the future.
Another notable outcome is the variable nature and extent of the shelf environment in different regions, the variability in geology, oceanographic conditions, geomorphological processes and preservation potential, and the differences of approach best suited to these different conditions. Already the outlines of a more detailed pattern of variability are beginning to emerge more clearly and this will surely provide an important step towards more sharply defined research questions, new field investigations, and improved standards for wide-ranging comparative analysis.
The topics covered in this volume are not only of scientific and intellectual interest, but central to some of the most pressing and practical concerns affecting our collective livelihood, prosperity and sense of common identity in the coming century – understanding of sea-level change and its likely trajectory and human impact, management of a massively increasing volume of digital records, and improved knowledge of how the now-submerged territories of the continental shelf have contributed to the early growth of our civilization.
Much remains to be done, and some of the geophysical knowledge that forms the necessary foundation for new investigation is highly technical. Nevertheless, the interested reader will find this volume an essential starting point for entry into a vast new intellectual, scientific and multidisciplinary territory. It is our hope and expectation that this will create the basis for an expanding field of future research in the coming decades, with improved integration of its multiple sources of information and expertise, an increasing number of participants, a growing investment of resources and funding, a new generation of marine scientists and archaeologists with the proper training to move across the borders of the traditional disciplines, and significant progress in advancing the new discipline of Continental Shelf Prehistoric Research.
Geoffrey N. Bailey
University of York, UK
Chair of SPLASHCOS
Dimitris Sakellariou
Hellenic Centre for Marine Research, Greece
Vice Chair of SPLASHCOS