Stratigraphic profile of the Pleistocene deposits in the eastern gallery of Denisova cave (2015 excavation campaign)

Field research of 2015 continued to study the outermost part of the Eastern gallery in Denisova Cave. We specified the stratigraphic sequence, educed the changes to the material compositions in previously marked out stratigraphic units and described their lithological content. Expedition determined as special aspects of separate layer structures well as the fact that post-sedimentological deformation of deposition had changed and had presented in other ways. The last fact probably evidences that regional climatic condition had changed. Three units, divided by clear-cut non-depositional hiatuses, form the sedimentological section, which filled the cave gallery. The upper unit (layer 9 and overlying Holocene deposits) is formed by light loess loam with lenses and single inclusion of debris and stone chips. These clay loams, especially Holocene deposits, are characterized by high organic content, which was the key for intensive chemotransfiguration of underlying deposit. The middle unit (layers 11-16) is presented by lensoid laminated block-chip material with mottled clay loam joining material. It formed after the opening-up the cavern under condition of intensive biogenic-anthropogenic impact against the spurted influence of regional climatic factors. The lower unit (layer 17) consists of ochreish yellow clay loam and heavy clay loam deposits with high inclusion of lime-rock particles, blocks and leached dripstones. Genetically it is the redeposited material, typical of the closed cavern (cave “terra rossa ”). Accumulation of this material is relevant to the most ancient stage of cave filling, when the cavern was closed for environments.