Zróżnicowanie petrograficzne i mineralne równowiekowych glin morenowych z wybranych obszarów Niżu Polskiego

Abstract

Petrographic and mine alogical diversity of the same age tills in the selected areas of the Polish Lowlands.S u m m a r y. Petrographic and mineralogical parameters of tills were studied in the region of Piła (NW Poland), Olsztyn (NE Poland) and Siedlce (E Poland). Lithostratigraphic zonation is introduced, based on values of petrographic coefficients. Petrographic parameters and heavy mineral composition of the tills differ between studied areas. Tills from the Piła region contain more resis tant mineralsb (49.60–1.2%), then non-resistant ones (21.9–46.2), while similar characteristics are typical only for the lower strata in the Olsztyn area. Also the glauconite content varies marekedly, from 0.6 % near Piła to 6 % near Olsztyn. The carbonate minerals are more abundant in the Olsztyn region (2.2–23.2%) than in the Piła area (1.3–7.1%). In all lithostratigraphic horizons of the Olsztyn region, the transparent minerals predominate over the opaque minerals. This tendency is less obvious in the Piła region (except for two horizons). Lower and upper lithostratigraphic zones, equivalent to Pleistocene chronostratigraphic stages, were recognized in borecore sections from the study areas.