The Pleistocene clastic sediments in the Divje babe I cave, Slovenia. Palaeoclimate (part 1)
Abstract The clastic sediments in the Divje babe I cave consist mainly of autochthonous terrigenous dolomite clasts, allochthonous terrigenous non-carbonate grains, and biogenic fragments, especially remains of the cave bear. These components are frequently cemented by apatite and subordinate calcite cement into aggregates (concretions) and into breccia. The formation and transformation of cave sediments were affected by climate and to some extent by the duration of sediment exposure to surface conditions on the cave floor. Congelifracts, a product of frost action, and cavernously corroded clasts, a result of corrosion by condensation and percolating water, were formed before being covered by younger sediments. Thus, the distributions of congelifracts and cavernously corroded clasts can be used to interpret climate changes in the period of 39.7 to 116.1 ka, with at least four hiatuses lasting from 9.0 to 39.7 ky. Based on the relative abundance of congelifracts, the palaeoclimate record can be correlated with global temperature changes established by oxygen isotopes δ 18 O from the Greenland ice. The succession C (cold)–H (humid), layers 2 to 11–12, is correlated with the lower part of OIS 3 and OIS 4, while the succession T (temperate)–D (dry), layers 12–13 to 23, is correlated with OIS 5.