Zasięgi i chronologia starszych nasunięć stadialnych lądolodu środkowopolskiego (saalian) między górną Wartą i Bugiem

Abstract

EXTENTS AND CHRONOLOGY OF EARLY STADIAL ADVANCES OF THE MID-POLISH (SAALIAN) ICE SHEET BETWEEN THE UPPER WARTA AND BUG RIVERS Summary A chronostratigraphic position and extents of stadial advances of the Scandinavian ice sheet are presented for the Odra Glaciation (the older glaciation of the Middle Polish glaciations, Saalian), in the territory bordered by the Upper Warta valley in west and the Middle Bug drainage basin in the east (Fig. 1). These advances are represented by separate tills and accompanying assemblages of glacial sediments and landforms, and were thermoluminescence dated (TL, Figs. 2-4). The earliest advance represents the pre-maximum, Krzna Stadial and occurred about 310,000-300,000 years BP. In that time the Scandinavian ice sheet reached the line connecting Przedbórz, Odrzywół mouth of the Kamienna River in the Vistula, Włodawa. The younger ice sheet advance represents the maximum, Kamienna Stadial and occurred about 290,000-280,000 years BP. During the maximum extent of the ice sheet during this stadial (Fig. 1), the ice bed occurred at 330 m a.s.l. in the northern margin of the Holy Cross Mts and got lower to 270 - 260 m a.s.l. at the slope of the Polish Jura and the Roztocze foreland. During the deglaciation after the Kamienna Stadial, oscillations of the ice sheet front occurred. They are expressed by the accumulated successively younger tills and formed end-morainic zones during the following two post-maximum stadials (phases) (Fig. 1). The age, at which the ice sheet reached its farthest extent during the first post-maximum stadial (phase), the Wieniawa one, was defined for about 270,000 -260,000 years BP. The farthest extent during the next post-maximum, Odrzywół Stadial (Phase), was dated for about 250,000 years BP. The following deglaciation after the Saalian-Odranian Glaciation resulted in exposing of the whole area from under the ice about 235,000-225,000 years BP, that is during the warming defined as the „Lublin Interglacial or Interstadial" or the „Grabówka Interglacial". This warming separates the mentioned glaciations from the Saalian-Wartanian Glaciation.