Introduction
The origins and scientific maturation of archaeology have always been closely related to developments in geology, and these parallel trajectories reach back to the times when Sir Charles Lyell, one of the founders of modern geology, published The Geological Evidences of the Antiquity of Man (1863) –conceivably the first book on geoarchaeology. Colin Renfrew (1976: 2) couldn’t put it more categorically when he noted that “since archaeology [...] recovers almost all its basic data by excavation, every archaeological problem starts as a problem in geoarchaeology”. Geoarchaeology is broadly defined as the application of principles and techniques of geosciences to archaeology (French 2003; Goldberg and McPhail 2006) and yet, ever since the term was first used in print (Butzer 1973), it meant to describe more than that (Butzer 2008). Some researchers opt to distinguish between geoarchaeology as archaeology conducted by methods of earth sciences, and archaeological geology, viewed as research that is primarily carried out for geological objectives but has implications for archaeological interpretations (see discussion in e.g. Waters 1992; Rapp and Hill 2006). For the purposes of this review we follow Goldberg and Macphail (2006) in considering the two terms as part of the same rubric, hence we see no need to differentiate them and we view geoarchaeology as a cross-disciplinary research domain that aims primarily at
(1) assessing the (chrono)stratigraphic context and integrity of archaeological sites
(2) reconstructing the landscape context of archaeological sites and the human-environment interactions, including human-induced landscape modification and land use
(3) understanding site formation processes
A full account of the definition, etymology or the disciplinary range of geoarchaeology falls outside the scope of this contribution (see e.g. Leach 1992; Waters 1992), as the way one wishes to delineate geoarchaeology and its applications depends on many different factors, including academic backgrounds and fields of interest –e.g. in North America geoarchaeology is mainly practiced by geologists, while in Europe mostly by archaeologists and geographers (Butzer 2008). All the same, we concur with Butzer (1982) and Renfrew (1976) who see a clear distinction between archaeometry and geoarchaeology and so we feel it reasonable to exclude from this review geophysical and geochemical research that deals with (1) archaeological prospection (remote sensing) (2) materials identification and provenance studies, and (3) chronometric dating methods. Geoarchaeology lies at the intersection of earth sciences with archaeology and, being ipso facto a multi- and inter-disciplinary endeavor, it encompasses disciplinary subfields with complementary and even overlapping agendas; consequently, deciding on which work is geoarchaeological or not is bound to be often blurred and more or less subjective. That being said, geoarchaeologists make use of techniques that derive from stratigraphy, sedimentology, pedology, geomorphology, micromorphology and geochronology.
As it is conceived and practiced today, geoarchaeology emerged hand-in-hand with the introduction of a positivist epistemology in the archaeological reasoning, which sought to make archaeology a ‘hard science’. The so-called New Archaeology of the 1960s and 1970s and the employment of the Middle Range Theory as a key concept of the processualist school (see Atici 2006) brought geology into play, as exemplified by the work of L. Binford (e.g. 1964, 1977), who emphasized the significance of investigating all processes –both cultural and natural– that affect the creation and post-depositional modification of the archaeological record. This realization laid the foundations for the development of a systemic, largely functionalistic and process-oriented methodological framework, in which context was the key-word: archaeology cannot reconstruct past human behavior before assessing first all geomorphic and anthropogenic agents that have potentially influenced the biography of the sedimentary matrix, in which the material culture is preserved. Thus, the study of what is now known as ‘site formation processes’ (Schiffer 1987) was one of the earliest targets of geoarchaeological applications. Contextual archaeology (sensu Butzer 1982) further promoted the conceptual and methodological convergence of archaeology with earth sciences, by advocating the study of past human behavior within an ecological framework, which linked archaeological interpretations with approaches from cultural/behavioral ecology, geomorphology and environmental history.
The application of geoscience techniques to archaeological investigations is undoubtedly linked more tightly to theoretical and methodological concerns born in prehistoric archaeology, rather than in the archaeology of historical periods. Due to a number of reasons that range from national policies (or even: nationalistic politics) to scholarly trends, funding interests and institutional objectives, archaeological research in Greece has been largely dominated by a persistent focus on the Classical, Hellenistic, Roman and Byzantine periods. As a result, historical archaeology –overall gripped by the perpetual power of classical studies and idiosyncratically practiced in Greece as art history– insulated the local scientific community from the new paradigm of processual and ‘science-based’ archaeology and functioned as a long-lasting buffer to Binford’s calls for viewing ‘archaeology as anthropology’, or Butzer’s advocacy of ‘archaeology as human ecology’. Nevertheless, credit should be given to a number of prominent Greek prehistorians, such as D. Theocharis (1919-1977) or G. Chourmouziadis (1935- ), who were ready to explicitly welcome such new ideas. Notwithstanding this historical estrangement of Greek archaeology from the natural-science-perspective, the peninsula of Greece came to be one of the few places where geoarchaeology was –on global standards– first practiced. This is not astonishing if we take into account that Greece is exceptionally rich in archaeological remains, while at the same time it is characterized by a remarkably complex geology and geomorphology.
The landscape of Greece has long been used as a natural laboratory, where famous scholars from various disciplines of both Earth Sciences and Humanities applied and tested their models, developed theoretical frameworks and elaborated on novel methodological approaches. The Aegean region and its surrounding areas comprise one of the most rapidly deforming parts of the Alpine-Himalayan belt (see e.g. papers in this volume), and as an active tectonic setting it has contributed profoundly to resolving fundamental issues in structural geology and plate tectonics, hydrogeology, geomorphology, and many other subfields of geology (e.g. McKenzie 1978; Le Pichon and Angelier 1979; Leeder and Jackson 1993; Jackson 1994; Bell et al. 2009). Tectonic activity restricted the development of broad alluvial reaches in Greece (Macklin et al. 1995). Coupled with a markedly seasonal climate, this configuration resulted in the development of a landscape that does not promote extensive ecological zonation. The prevalence of mosaic environments, with a striking heterogeneity and a variety of diverse ecological resources over short distances, has attracted the interest of ecologists, paleoclimatologists and biogeographers (e.g. Tzedakis et al. 2002; Medail and Diadema 2009). Major researchers working in the domain of prehistoric or landscape archaeology were soon to appreciate the opportunities that this highly ‘broken-up’ ecogeographic setting offers for the unraveling of key aspects in human-environment relationships. For example, Claudio Vita-Finzi, a geographer, and Eric Higgs, a prehistorian, advanced the method of ‘site-catchment analysis’ during their work in the rugged relief of Epirus, initiating a long-lasting tradition of ecological/landscape approaches in the study of hunter-gatherer economy, which draws much attention to the topographical and geomorphological attributes of the landscape by focusing on such parameters as the availability, spacing and seasonality of plant, animal and mineral resources in determining prehistoric site locations (Higgs and Vita-Finzi 1966; Higgs et al. 1967; King and Bailey 1985; Bailey et al. 1993; Bailey 1997). In these lines, it comes as no surprise that all four major North American geoarchaeologists, namely K. Butzer, W. Farrand, G.R. Rapp and J.C. Kraft, “who played important roles in building geoarchaeology into a discipline” (Rapp and Hill 2006: 20) have worked in Greece, some of them early in their career and in decades-long research projects.
The following review of geoarchaeological research in Greece is structured along a dual axis, which brings together both a chronological ordering and a thematic grouping of the relevant investigations. As we see it, geoarchaeological applications can be grouped into two main categories: one that involves regional or landscape-scale studies, and another one that entails on-site research with micro-stratigraphic, sedimentological and micromorphological analyses at the scale of the individual site. With this distinction in mind, we have reviewed the latter group of studies separately (section 5) and yet from a historical perspective, as with the case of the preceding sections. As noted above, pinpointing the beginnings of geoarchaeological approaches is a relatively subjective task, since the blending of geosciences methods with those traditionally ascribed to archaeology has been time-transgressive and, in a broad sense, it reaches back to the very foundations of the two disciplines and their subfields. Similarly, for a number of reasons if not simply due to space limitations, it is inevitable for any review of this kind to include only part of a broad spectrum of published studies. For those and for any other unwillingly-occurring omissions, we ask for the reader’s understanding.