Abstract:
The Moskowian glacial horizon of the middle Pleistocene is distinguished in the center of the Russian Plain, and, despite a large distribution area, it is poorly studied lacking, for example, the universally adopted regional scheme of its stratigraphic subdivisions. The suggested subdivision of the Moskowian glaciation into several stages is a result of a detailed study of several sections in the Mozhaisk-Tarusa glaciation radius. The best defined are the Borovsk, Kaluga, Mozhaisk and Krasnyi Kholm stages divided by warming phases of different rank. The analytical (lithological-mineralogical and spore-pollen) data, in combination with results of the radiothermoluminescent (RTL) dating, show that the time span between the first and the second (Borovsk and Kaluga) stages was the longest and distinct owing to considerable changes in the spore-pollen spectra of the cool to moderately warm type close to those of the interglacial phases. This interval is ranked and named as the Protvino Megainterstadial. Sediments of this interval are widespread and can be correlated with the deposits of the Kostroma interval recognized earlier in the middle Volga region. The obtained data allows a reliable identifying of three large stages in the Moskowian epoch: the early and middle Protvino, and the late Moskowian stages.