Lacustrine transgressions in the Late Cenozoic Ussuri-Khanka depression (Primorye)
The features of Quaternary alluvial-lacustrine and lacustrine sediment genesis in the Ussuri-Khanka depression developing in conditions of transgressive accumulation as a result of tectonic subsidence and numerous fluctuations of climate are considered. The basic role of alluvial dams and irregular accumulation is proved in the genesis of lakes within the depression. The dependence of lacustrine reservoirs level fluctuations on climatic fluctuations is shown. The new data confirming lacustrine genesis of the most part of Khanka depression section referring to the Middle Pleistocene-Holocene are adduced. Two transgressive phases with the rise of the lake level by 1.5-2.0m above the present one for the Subboreal are established. The general conclusion is that mesorhythmicity of the sedimentary sequence fixed in the Ussuri-Khanka depression reflects its dependence on climatic fluctuations in the Late Cenozoic.