Title : Fairy Tales and facts about the environmental magnetism of the Siberian loess sequences
Abstract:
The Siberian loess province is comparable in area to the well-known Chinese loess plateau. However, until now, this area remains practically unexplored. Since the publications by Chlachula et al.(1997-2003) western researchers have formed a stable opinion that the formation of the magnetic properties of the Siberian loess-soil series proceeded by the same mechanism as in the Alaskan loess-soil series. This opinion is mainly based on the data from Kurtak section which characterizes the northernmost (excluding edoma deposints of Lena river and Chukotka) area of loess distribution in central Siberia and, therefore, these data should not be extended to the areas of Western and Eastern Siberia located to the south. The buried soils in Western Siberia are well developed (up to the chernozems) and their magnetic characteristics indicate the presence of superparamagnetic grains and, consequently, active pedogenesis. Thus, concentration dependent rock magnetic parameters in those strata follow “wind-vigour” mechanism (like in Alaska: whereas the structural-sensitive parameters follow the "pedogenic" mechanism (as in China).Such a superposition of mechanisms we singled out as a "Siberian mechanism". This mechanism works throughout Western Siberia, and in areas with different climatic conditions, one can trace a different contribution of the "pedogenic" and "wind-vigour" components to the total magnetic signal. Buried soils In Eastern Siberia are less developed, so the "pedogenic" component in "Siberian" mechanism is weaker. In Early Pleistocene soils of Eastern Siberia, “Siberian mechanism turned to pure "pedogenic", whereas in Central Siberia, the "wind-vigour" mechanism changed to the "Siberian" mechanism with a pronounced "pedogenic" component.
The research presented here was supported via research grant from the Russian Science Foundation No. 19-17-00216
