Podstawy podziału zlodowacenia północnopolskiego

Abstract

PRINCIPLES FOR DIVISION OF THE NORTH-POLISH GLACIATIONSummaryThe division of the North-Polish Glaciation is based on the changes in climatic conditions which are, first of all, reflected in the development of flora and in the character of geological processes.The sections examined from the palaeobotanical point of view, in which the deposits with flora occur, allow us to distinguish in the North-Polish Glaciation a long and relatively warm interstadial period. The flora of this interstadial is known from Konin, where it is best developed and occurs in the precisely determined geological conditions (Z. Borówko-Dłużakowa, 1967; E. Rutkowski, 1967), from Wadowice (M. Sobolewska, L. Starkel, A. Środoń, 1964), from Brzeziny (K. Birkenmajer, A. Środoń, 1960) and from Podgłębokie (Z. Janczyk-Kopikowa, 1968; J. E. Mojski, J. Rzechowski, 1968). According to a univocal opinion of palaeobotanists and geologists, it belongs to the Brorup Interstadial. A well developed fossil soil found in the Polish loesses (J. E. Mojski, 1967, 1968) and in the periglacial covers in the vicinity of Łódź (B. Manikowska, 1966) is of similar age.The Brorup Interstadial divides the North-Polish Glaciation into two stages: older, known as the Szczecin Stage, and younger, named the Main Stage (E. Rühle, 1965). The Szczecin Stage is represented by a loess horizon, periglacial slope covers and, probably, glacial deposits in the northern part of the Polish Lowland area. On the other hand, to the Main Stage belong glacial and fluviogiacial deposits of Leszno, Poznań and Pomeranian phases, loess deposits, periglacial slope covers, as well as lacustrine and fluvial deposits. These formations particularly, however, the loesses (J. E. Mojski 1967, 1968) and glacial deposits (R. Galon 1957, 1961) are at least bipartite. The sections examined in great detail prove a subdivision of the Main Stage into six phases and five interphases.