Pozycja stratygraficzna tarasów Dunajca w Karpatach Zachodnich

Witold Zuchiewicz

Abstract


STRATIGRAPHIC POSITION OF QUATERNARY TERRACES IN THE DUNAJEC RIVER VALLEY, POLISH WEST CARPATHIANS

Summary
The paper discusses stratigraphic position of Quaternary terraces of the Dunajec River, Polish West Carpathians, within a number of geomorphic units, i.e., the Pieniny Mts. (Fig. 1), Beskid Sądecki Mts., Łącko – Podegrodzie Foothills, Nowy Sącz Basin (Fig. 2), Beskid Wyspowy Mts. and Rożnów Foothills (Fig. 3). The valley sides bear flights of strath, cut-and-fill, as well as fill terraces, mostly of the complex-response type, that have been formed under both climatic and tectonic conditions. These flights include 9 Pleistocene and 2 - 4 Holocene terrace steps, the age of which is still a matter of debate (cf. Table I). A new allostratigraphic scheme has been proposed, consisting of 6 alloformations and three allomembers (cf. Table 11) that are tentatively correlated with the Praetiglian, Eburonian, Menapian, Elsterian-1, Elsterian- 2, Drenthe, Warthe, and Vistulian stages. The oldest Pleistocene terrace treads rise 100 - 160 m above the valley bottom; the lowest ones do not exceed 6 - 8 m in relative height. A glacial age of alluvial cover is evidenced by intertonguing of fluvial and solifluction deposits, whereas climatostratigraphic correlation is enabled by the presences of glaciofluvial material within those terrace covers in the Rożnów Foothills that were formed at the time of maximum advance of the Scandinavian ice-sheet, i.e. during the Elsterian-2 (Sanian) stage. These terrace treads can be easily traced thoughout the valley, up to glaciofluvial fans shed in the Podhale region during the oldest glaciation in the Tatra Mts. The remaining terrace steps may, hence, be classified according to their position in relation to the Elsterian-2 (Sanian) treads, as well as by using lithostratigraphic criteria and considering facies transition between fluvial and slope covers. Future stratigraphic studies should focus on magneto-,pedo-, and palynostratigraphic aspects of both fluvial and slope deposits.