Lithostratigraphy and genesis of Quaternary strata between Lanckorona and Myślenice in the Western Outer Carpathians

Abstract

The region between the Wieliczka Foothills and the Beskid Makowski Mts. has yielded new data on the accumulation of loess-like deposits during the Vistulian Glaciation. The grain-size distibution and the heavy mineral composition, particularly the significant presence of amphiboles, indicates on aeolian origin for these silty deposits. The silt was most probably derived from glaciofluvial deposits in the Carpathian forelands. Among the Quaternary deposits which accumulated during the Vistulian Glaciation and Holocene, three horizons of loess-like deposits (correlated with the lower, middle and upper younger loesses of the Lublin Upland), three horizons of solifluction deposits, and three horizons of deluvial deposits were distinguished. The accumulation of seven alluvial successions in the Raba and Harbutówka River valleys encompasses a large part of the Quaternary - from the South Polish Glaciations (terraces VII and VI) up to the Holocene (terraces II and I). The lithostratigraphy of the slope deposits (solifluctional and deluvial) and loess-like deposits has been estabilished mainly on the basis of 14 C dates of the palaeosol horizons. One of these dates, combined with palynological analysis, confirmed the existence of a warmer period in the Denekamp Interstadial (31 200 +/- 1000 years BP in the Harbutowice-1 section). The dates obtained from +/-he Jastrzębia-1 (20 760 +/- 300 years BP) and Polanka-1 (20 980 +/- 310 years BP and 14 510 +/- 150 years BP) sections point to periods favouring the development of soils in the younger and terminal parts of the Younger Pleniglacial. These results, consistent with the dates obtained by other investigators, point to the existence of a warmer period (between 24-20 ka BP) in southern Poland during the maximum development of the ice sheet (Main Stadial) during the last glaciation in northern Poland.