Irini Sifogeorgaki will present the PG Seminar with a talk entitled "Geoarchaeological insights on site formation processes of sandstone and quartzite rockshelters and the Umhlatuzana case study (KwaZulu-Natal, South Africa)".  

In South Africa, numerous archaeological sites are developed on sandstone and quartzite rockshelters. While karstic cave and rockshelter deposits have been intensively studied, similar contexts in siliceous bedrocks (sandstone and quartzite) are comparatively overlooked.

In this talk, Irini will first provide an overview of the unique characteristics of siliceous rockshelters. Secondly, she will talk about the ongoing geoarchaeological research on Umhlatuzana rockshelter, focusing on the geoarchaeological techniques applied (mainly micromorphology, grain size analysis, sediment pH analysis, X-ray fluorescence). I will mention the reason why those techniques were selected and will discuss main results and interpretations. Next, I will compare the Umhlatuzana rockshelter formation processes to geoarchaeological studies in a similar context. Finally, I will discuss a workflow for researchers (both archaeologists and geoarchaeologists) working on sandstone and quartzite rockshelter excavations to fully assess the depositional and post-depositional processes.

About the presenter:

Irini Sifogeorgaki is a PhD student at Leiden University conducting geoarchaeological research within the “Finding resolution for the Middle to Later Stone Age transition in South Africa'' project. Her work focuses on determining Site Formation Processes of the Umhlatuzana, Umbeli Beli, and Shongweni rockshelters, all of which are located in KwaZulu-Natal, South Africa. Her study addresses scientific debates about the South African Stone Age and aims to generate knowledge on global climate fluctuations during the Pleistocene and their regional expressions. To proceed with the geoarchaeological assessments, micromorphological analyses are combined with micro stratigraphic bulk sediment analysis (pH, granulometry, Loss on ignition, X-ray Diffraction). The research targets various types of occupational information, stratigraphic and sedimentological irregularities, examination of minerals to determine diagenetic situation, and study of sediment origin within the landscape. In addition, Irini is conducting raw material analysis of the rockshelter’s lithic assemblages.