Про змінення положення південної границі Дніпровського (риського) зледеніння

Abstract

On the basis of newly discovered factual material, this paper analyses the issue of the reassigning the position of the southern border of distribution of the Dnieper (Riss) glacial tongue, which is considered the southernmost glacier tongue of the glacial period in Europe. The article provides critical analysis of the history of glacial theory and the contribution of scientists from different countries. The article analyses the evolution of the views of researchers - from the drift origin of boulder-loam deposits, described in works by R Murchison, C Lyell, D Tilas and C Darwin, to the idea of glacial origin, the first supporters of which included Pierre Martel, Jean-Andre Deluc, Bernhard Friedrich Kuhn, Ignaz Venets , Albrecht Bernardi, Louis Agassiz and others. The paper evaluates the contribution of Russian scientists who studied continental glaciations, including P O Kropotkin, S M Nikitin, O O Inostrantsev, P Y Armashevsky, N I Krishtofovich, G E Shurovsky, F B Schmidt and others. The article also presents the position of V G Pazynych, an opponent of glacier theory, on the numerous differences of opinion in the interpretation of the framework of the theory and on the necessity of developing a complex model of glaciations, which would include consideration of both exaration and drift. This article presents for the first time the results of solving the problem of restoring the geological relic, the “Domotkanski valuny” [lit. Domotkan boulders – translator`s note] as an important object of geological heritage on the southern border of the Dnieper glacial tongue. The paper presents a study of Kalytva mountain as a terminal moraine formation, which was formed during the Dnieper glacial epoch. Kalytva mountain is a fine example of manifestations of glaciotectonic activities, moraine,fluvio- and limno - glacial deposits with erratic boulders and paleogenic outliers. The article proves the possibility of division of the Dnieper climatolith into lower, -middle, and upper Dnieper stadials and shows the correspondence of limno-glacial deposits, moraine and fluvio-glacial deposits of the middle Dnieper stadials to the upper part of the “Shevchenkivska suite”. We have shown that the periglacial zone situated to the south of the line Volnohorsk-Petrykivka-Yurivka is characterized by absence of boulder loams, by much more homogenous and weathered section of sub-aerial Quaternary deposits and by a lens of fluvio-glacial deposits. The discovery of the artificial outcrop of limno glacial moraine deposits between Spasske and Podhorodne villages enables us not only to determine the main clearly-manifested differences between eolian and limnetic loams but also to delineate more precisely the borders of the periglacial zone of the Dnieper glaciations, which was earlier marked almost 100 km to the north – in the region of the Orel river far from its confluence with the Dnieper. Field studies in the interfluve between the Dnieper, Kilchen and Samara found significant evidence for proving that the southern border of the periglacial zone of the Dnieper Glacial Epoch lies considerably further south than had been assumed previously.