ИСТИНА

Loess deposits of the Lower Volga region of Russia are characterized by the alternating influence of marine and continental environments. The continental sedimentary material consists of thick loess-palaeosol sequences describing the climate and environmental conditions of regressive stages during the evolution of this region of the Caspian Sea [1]. The chronology of these sediments has received very little attention compared to that given to the under- and overlying marine deposits; as a result even the definition of the continental deposits remains under debate. Periods of continental sedimentation during regressive phases are represented by fluvial sands and by more silty, apparently sub-aerial, deposits in the Lower Volga region. A thick and detailed loess-palaeosol sequence is recorded at Leninsk location in two outcrops. In 14 m of Leninsk I 10 horizons were identified and in Leninsk II a further 4.55 m sequence was described starting from the paleosol 4 (PS4). A total of 39 samples were collected for luminescence dating. All measurements were made on multi-grain aliquots. Quartz dose estimates were made using a standard SAR protocol; K-feldspar dose estimates were measured using the post-IR IRSL290 SAR procedure. Radionuclide concentrations were measured using high resolution gamma spectrometry.