Reconstructions of Paleowind Directions in the Pleistocene: Evidence from the Anisotropy of Magnetic Susceptibility of the Loess–Paleosol Series of Tajikistan and the Azov Region

Abstract

Abstract—The magnetic fabric of the reference Khonako-II (south Tajikistan), Beglitsa, and Chumbur-Kosa (Azov region) loess-paleosol sections was studied to reconstruct the paleowind directions during the Middle and Upper Pleistocene. The paleosols and loesses of the Khonako-II section represent a promising object for study of paleowinds. Our data indicate a prevailing ~ northwestward or ~northeastward wind directions during accumulation of the upper 40.8 m of the section. Thereby, a change from warm (pedocomplex 2) to cold (loess 2) epochs during the accumulation of the lower half of the studied sequence (end of the Middle Pleistocene) was accompanied by “switching” the predominant winds (from northwestern to northeastern ones), whereas accumulation of the upper part of the sequence was mainly controlled by winds of intermediate directions. The latter can be considered as evidence for the lesser contrast of wind rose during later epochs that were responsible for the formation of the upper part of the sequence. The study revealed that the magnetic fabric of loess and paleosol horizons of the Azov region sequences was deformed and cannot be used for paleowind reconstruction. It was demonstrated that sampling using plastic container technique widely applied in studying loess–paleosol deposits could led to the significant deformation of primary magnetic fabric.