GEOARCHAEOLOGY OF CAVE SEDIMENTS FROM THE OLD WORLD: AN HISTORICAL PERSPECTIVE

The geoarchaeological study of cave sediments dates back to at least the 1940s and 1950s with François Bordes and his students at Bordeaux. Transporting methodologies to investigate Quaternary loesses in the Paris Basis, he and geologists like Henri Laville studied the sedimentology of these deposits, focusing on paleoenvironments and climatostratigraphy, with the aim of correlating Palaeolithic cave sequences. They employed techniques such as granulometry, pH, CaCO₃ content, morphology of limestone clasts, as well as some elemental geochemistry; similar types of studies were applied to Syrian cave and rockshelter sites (Jerf ‘Ajla and Yabrud) with limited success. In the early 1970s while analyzing the sediments from et-Tabun (Israel) I realized that these methods were missing the target and were largely inadequate in the investigation of site formation processes there, particularly for the upper deposits, which were composed of ashes resulting from large fires made by Neanderthals. Later research at Kebara and Hayonim Caves (Israel) in the 1980s and 1990s, Pech de l'Azé IV and Roc de Marsal in France (2001-9), as well as at Sibudu in South Africa in 2009, showed that anthropogenic inputs and modifications (accompanied by significant diagenesis) represent major depositional aspects of the deposits, constituting a scant majority of the cave fill, particularly at Sibudu and Kebara. During these past few decades the technique of micromorphology has advanced to the point that it is one of the most effective means to isolate and understand the individual effects of geogenic and anthropogenic processes that commonly occur synchronously in these cave sites. It should be used routinely as a first step in analyzing cave and archaeological sediments, as most classical sedimentological techniques are inappropriate for these organic-rich anthropogenic and geogenic mixtures of deposits.