QUATERNARY LOESS-PALEOSOL STRATIGRAPHY OF CENTRAL ASIA: GEOCHRONOLOGY, CORRELATION, AND EVOLUTION OF PALEOENVIRONMENTS

Abstract

Loess-paleosol covers are widespread in Central Asia. The most complete loess-paleosol sections are situated in southern Tajikistan. By using biostratigraphic and paleomagnetic records, we recognized the main stratigraphic units of the upper Pliocene and Pleistocene in the sections. The thermoluminescence analysis and correlation of loess-paleosol successions to the oxygen isotope scale are used to obtain the refined loess-paleosol geochronology of Central Asia. Thorough measurements of magnetic susceptibility (K) of paleosol and loess horizons revealed structural peculiarities of individual soil beds. Data on climatic fluctuations inferred from the loess-paleosol successions are in accordance with the oxygen isotope records. The loess sedimentation is shown to be closely related to the atmospheric circulation and synoptic phenomena.