ABSTRACT. We discuss the radiocarbon chronology of the loess deposited during the Upper Pleniglacial (Isotope Stage II) for the key site of Cosautsi (Republic of Moldova), which presents some major problems in 14C dating. Special care was paid to accurate microstratigraphic positioning of samples, collection of top-quality material (mainly conifer charcoal), and selection of uncontaminated pieces for dating and crossdating with bones by accelerator mass spectrometry (AMS) and/or conventional 14C dating. The results provide reliable and precise information on the sedimentation processes, the succession of short climatic events and the cycle of recurrent human settlements on the site between -20,000 and 16,000 BP. Two sets of climatic improvements can be ascribed to interstadial oscillations named, successively, Cosautsi VI (19,000 BP) and Cosautsi V (18-17,500 BP).

The East Carpathian regional sequence established for the middle and late pleniglacial loess is based on records from the Palaeolithic sites Molodova V (Ukraine), Mitoc-Malu Galben (Romania) and Cosautsi (Moldova). The special importance of this long sequence lies 1) in the high quality of the pedosedimentary and climatic records favoured by the position of the three sites within the terrace system of the Driester and Prut basins and 2) in the high chronological resolution within the period posterior to 33,000 BP determined by the archaeological context of the multilayered Palaeolithic sites. A large number of these layers with a quite regular distribution within the sequence appeared to be rich m good quality organic material for accurate radiometnc dating. This made possible to establish a well documented pedosedimentary and climatic succession encompassing the main part of the middle pleniglacial and almost the whole upper pleniglacial, with a resolution degree around one millennium or several centuries. The analysis of this new sequence revealed a quite coherent internal structure that illustrates the complexity of the sedimentary and climatic dynamics within the time span 33,000 -10,000 BP.