The tectonics and stratigraphy of the transitional zone between the Pieniny Klippen Belt and Magura Nappe (Szczawnica area, Poland)

Abstract

The Pieniny Klippen Belt is a narrow, complex structure stretching along a tectonic boundary between the Central and Outer Carpathians. Its formation involved two main evolutionary stages, the first, related to Late Cretaceous-Paleocene folding and thrusting, and the second, associated with Miocene orogenic events in the Outer Carpathians. Interactions between the Pieniny Klippen Belt and Outer Carpathians during both the sedimentation and deformation stages have resulted in the establishment of a peri-klippen transitional zone (named the Šariš Transitional Zone), in which the tectonic deformation effects gradually decrease towards the north. The stratigraphy and tectonic position of this zone have been controversial for decades. The key stratigraphic problems concern 1) the lithologic identity and position of the Szlachtowa (»black flysch«), Opaleniec and Pieniny formations and 2) the relation of the Jarmuta Formation, associated mainly with the Šariš Transitional Zone, to the Szczawnica and Zarzecze formations of the Magura Nappe. We provide an early Paleogene dinoflagellate cyst stratigraphic record of deposits that, according to some recent reinterpretations, represent the Neogene »Kremna Formation«. The legitimacy of new lithostratigraphic assignments of the »Kremna Formation« at Jaworki is put into question upon the basis of the primacy of units introduced for the same strata earlier.