Microfacies Analysis of Cherts in Upper Palaeolithic Sites Along The Lower Danube Valley (Romania)

Abstract

This article focuses on the petrographic analysis of chert samples from the Lower Danube Valley, Romania, between West of Olt Valley and East of Mostiştea Valley (Upper Palaeolithic sites and modern quarries in gravels of Frăteşti Formation and Danube terrace deposits). Macroscopic examination of hand specimens established visual characteristics of cherts and allowed the primary separation of samples. Microfacies analysis was carried on 116 thin sections, with special attention to grain categories, recognition of systematic fossil groups, matrix, and cement types, estimated by use of visual comparison charts for each thin section. Bulk dominant mineralogical phases were determined through X-ray diffraction on 82 samples. Microfacies analysis provided the means to characterize and classify cherts from the Lower Danube Valley (22 chert microfacies), demonstrating that raw-materials were previously inadequately characterized and defined too generally. Also, this study confirmed older hypotheses about local alluvial deposits as supply sources for some of the Upper Palaeolithic sites.