Challenges for a cross-disciplinary geoarchaeology: The intersection between environmental history and geomorphology

Abstract Geoarchaeology is a growing subfield of cross-disciplinary research at the intersection between geomorphology, environmental history, and archaeology. This prospective essay does not aim to analyze the nature or evolution of geoarachaeology, or to review available techniques and methods. Instead it addresses challenges . Exciting challenges confront geoarchaeology in the form of persistent problems that demand satisfactory solutions, despite improving skills and innovative technologies. Drawing from the full record of human history, a number of practical issues can be highlighted to explicate these challenges: (1) Open-air archaeological sites are the main object of study for the Early to Mid-Pleistocene, even though they represent open systems that raise fundamental questions about archaeo-taphonomic integrity. How were sites buried and then modified by selective preservation, horizontal or vertical disturbance, and the role of carnivores? Is it possible to determine the degree to which such sites accurately record prehistoric human behavior, prior to the Late Pleistocene when hearths and living structures lend better definition to occupation surfaces? Can non-primary open-air sites also shed light on human activities and environmental history? (2) Cave sites have long been favored by archaeologists because of the impression that they represent relatively complete and undisturbed archaeostratigraphic sequences. But serious problems also exist here in regard to the nature of accumulation and the sources of mineral and biogenic sediments in what were open systems, liable to disturbance, despite comparatively low-energy processes. (3) Less familiar are urban and other architectural sites, where processes of formation and degradation mimic natural sedimentation and erosion. Such a geoarchaeology can be highly informative for urban processes, demographic cycles, or the intersection between sites and their surrounding landscapes. (4) Spatial components of geoarchaeological research need more systematic consideration, for locational strategies and with an appreciation that site presence or absence allows a more dynamic modeling of settlement and procurement strategies. (5) Regional settlement expansion and contraction may also inform on mosaic evolution or Pleistocene dispersals, including the Out of Africa hypothesis. (5) Finally, multiple themes connected with environmental degradation during Holocene times may open new windows to examine specific problems by objective criteria, so contributing to a wider academic discourse about long-term trends, the interfingering of climatic and land-use factors in cause-and-effect dilemmas, or the construction of future scenarios in an era of accelerating planetary change. The focus of archaeology is shifting to later ranges of prehistory so that geoarchaeologists now have a mandate to engage more directly with urban, spatial, and degradation issues. This should be met with a broader and more inclusive agenda, one that optimizes on expertise with historical geomorphology and environmental history, but in collaboration with archaeologists and other social scientists. That would sustain a more prominent role for geoarchaeology in the university curriculum.