Specific features of geological and geomorphological structure of quaternary deposits in the coastal bluffs of the left bank of the Krasnoyarsk reservoir near the Sabanikha-3 and Sidorikha sites

The article discusses the results of geological and geomorphological research of the Upper Paleolithic sites Sabanikha-3 and Sidorikha and nearby outcrops on the left bank of the Yenisei River in the Bogradsky District of the Republic of Khakassia in 2022. Sabanikha-3 is classified as the Initial Upper Paleolithic site, while Sidorikha is the Final Upper Paleolithic site. Both are located on the coastal bluffs within the bays of the Kranoyarsk Reservoir bounded by rocks. A detailed analysis of the sediment structure of the Sabanikha-3 and Sidorikha sites allows distinguishing three main lithotypes that form these sections. Two lithotypes are water- and mud-stone varieties of debris flows. The deposits of the third lithotype-parallel layered well-washedfine-, medium-coarse-grained sands with interlayers of shingles are located. The deposit structure suggests the participation of glacial super-floods in their formation, and similar results have been recorded on the right bank of the Ob River, on the Pre-Altai plain. Superfluvial deposits are also identified in the Kyzyl extension of the Upper Yenisei and in the South Minusinsk Basin. All of these suggest that undisturbed stratified Paleolithic sites should be explored in brown subaerial covers of typical loess lithology outside the superfluous splashes. In the sandy subaerial covers, the sites of the final stage of the Upper Paleolithic (the Sidorikha site) should be expected on top of superfluous deposits of the end of the last glacial maximum. In its turn, Sabanikha-3 is an example of the site confined to the sandy subaerial cover, which lies on the superfluvial stratum of the first glaciation of the Upper Neopleistocene. In general, the Krasnoyarsk Reservoir area is the most promising for searching sites of the final Upper Paleolithic, and more ancient sites can be found in the areas where MIS-3 subaerial covers have survived erosion.