Paleosol complex in the uppermost Mikhailovian Horizon (Viséan, Lower Carboniferous) in the southern flank of the Moscow Syneclise

Abstract

The beds composing an unconformity at the boundary of the Mikhailovian and Venevian horizons in the Polotnyanyi Zavod quarry (Kaluga Region) are investigated. A detailed study has shown that, at the base of black “rhizoid” limestone, a pedocomplex of two paleosols of different genesis is formed. From below upwards, rocks of subaerial (Paleosol 1 of the rendzina type), subaerial–subaquatic (Paleosol 2 on bog marl), and palustrine genesis replace each other. Both paleosols display a horizontal structure of profiles; the presence of the root systems, imprints of plants, and traces of animal’s activity; the presence of soil new formations (micritic calcite with a light isotopic composition of C, Fe-concretions ). In paleosols, some geochemical indices (PWI, CIA, CIA-K), the ratios Ba/Sr, Rb/Sr, and concentration of Ga increase. The soil complex was formed under conditions of a warm subhumid climate. In the structure and lateral scale of distribution, the object investigated is comparable to the Everglades marsh landscape of Florida (United States).