Northern Urals (Russia) quaternary deposits and biostratigraphical record caves and grottoes

Abstract

Investigations of the unconsolidated Upper Pleistocene – Holocene cave deposits of the Northern Urals resulted in detailed biostratigraphical and palaeoenvironmental data. The article summarizes data from important stratigraphical levels exposed in 19 cave localities, most part of which represent several layers dated to different periods. These data cover the period from the beginning of the Upper Pleistocene (MIS 5-4) to the end of the Upper Holocene. At the beginning of Marine Isotope Stage 3 (MIS 3), open woodlands were distributed, which at the end of MIS 3 were replaced by Forest–steppe landscapes. At the beginning of MIS 2 (LGM), Periglacial steppe landscape was distributed. At the end of MIS 2 and at the beginning of the Holocene (MIS 1), semi-open landscapes were common. At the beginning of the Middle Holocene, they were replaced by taiga landscapes. Fish were present in the fauna of the Northern Urals in the Upper Pleistocene and Holocene. Amphibians in the Upper Pleistocene as part of the fauna of the region appear only at its beginning (MIS 5-4) and end (Bølling – Allerød period). Since the beginning of the Holocene (MIS 1), they have been constantly present in the fauna of the Northern Urals. Reptiles appear in the fauna of the region only in the Middle Holocene. During the Upper Pleistocene, the avifauna and fauna of small mammals were dominated by species of open landscapes, and the fauna of large mammals was dominated by species of open and semi-open landscapes. At the beginning of the Holocene, the avifauna and theriofauna increased the number of species associated with tree and shrub vegetation and near-aquatic species. Since the beginning of the Middle Holocene, the avifauna and theriofauna have been dominated by species of taiga landscapes. Palynological data and data on the fauna of small and large mammals allow us to separate the deposits of the Upper Pleistocene and Holocene. These data also allow us to separate the deposits of the beginning (MIS 5-4), middle (MIS 3), end (MIS 2)) of the Upper Pleistocene, Lower, Middle and Upper Holocene (MIS 1).