What is geoarchaeology?
Geoarchaeology is a field of study that applies methods from the Earth sciences to answer archaeological questions. In a fundamental sense, all archaeological investigations are also geological because material remains are buried and/or preserved in geological settings. It is thus important for archaeologists to understand not only the relationship between archaeological materials and the sedimentary contexts from which they were recovered, but also how past geological processes (e.g., erosion, sediment accumulation) influenced the formation of the archaeological record that we observed today. Geoarchaeology also provides a suite of techniques for reconstructing past environmental conditions. These tools are essential for modern archaeological research to better understand how past humans interacted with and adapted to their environmental surroundings over time.
What does a geoarchaeologist do?
Geoarchaeologists uses principles and methods from the Earth Sciences (geology, geography, geomorphology, geophysics, geochemistry) to understand the formational history of archaeological sites. Once materials were discarded/deposited in the past, a multitude of geological processes could influence the preservation and distribution of archaeological remains over time. By analysing sediments and stratigraphy of archaeological sites, geoarchaeologists can identify these ‘post-depositional’ processes and disentangle site formation history. Geoarchaeologists also apply techniques to study archaeological remains in high-resolution under a micro-context to identify microscopic traces of past activity events (such as fire use) that are otherwise difficult to observe with our naked eye. These techniques include micromorphology, Fourier transform infrared spectrometry (FTIR), scanning electron microscopy (SEM), micro X-ray florescence (micro-XRF) and magnetic susceptibility. This microcontextual approach, which has been called microarchaeology, is rapidly becoming a vital part of modern archaeological research.
What do we do at CAS?
CAS members apply geoarchaeological techniques to understand the geological context of archaeological sites around the world, from Australia to Southeast Asia, China, Siberia, Jordan, South Africa and Europe. These studies are often carried out in conjunction with archaeochronometric research for constructing archaeological chronology within the context of site formation processes. CAS features a dedicated Geomicroscopy laboratory that is used for archaeological micromorphology analysis, and a MicroTrace laboratory with Raman spectroscopy and Fourier transform infrared spectrometry (FTIR) for characterising the geochemistry of archaeological sediments as well as identifying organic residue on archaeological materials. CAS also has a close affiliation with the GeoQuEST Research Centre at UOW, which houses state-of-the-art geochemistry facilities such as Laser Ablation ICP-MS, X-ray florescence, and X-ray diffraction. These facilities are invaluable for characterising the geochemistry of archaeological remains and sediments.