Popękane klasty w stożku Domańskiego Wierchu: Przyczynek do rekonstrukcji ewolucji pola naprężeń w rejonie Kotliny Orawskiej (Karpaty) podczas neogenu i czwartorzędu
Abstract
FRACTURED CLASTS IN THE DOMAŃSKI WIERCH SERIES: CONTRIBUTION TO STRUCTURAL EVOLUTION OF THE ORAWA BASIN (CARPATHIANS, POLAND) DURING NEOGENE THROUGH QUATERNARY TIMES
Summary
Orawa Basin is an intramontante basin filled by fresh water Neogene and Quaternary strata. Part of the basin fill is the Upper Miocene-Pliocene Domański Wierch series. Within the series, clasts (up to 1.3 m across) are commonly fractured. In particular exposures, these fractures occur as a single set of extensional joints or as two sets of shear fractures conjugated under small dihedral angle. The fractures were formed due to regional stress field with the maximum stress axis (δ1) horizontal and trending NE to NNE.It follows from the analysis of tectonic deformation in the Orawa Basin substratum, that a similarly oriented stress field occurred in the discussed area during Middle Miocene time. Moreover, results of breakout analysis in the area indicate that similarly oriented stress field occurs there at Present. It is concluded therefore, that the stress arrangement within the Orawa Basin region has not undergone significant rotations, since Middle Miocene times. This stress arrangement has been characterized by horizontal δ1 trending NE to NNE.
Summary
Orawa Basin is an intramontante basin filled by fresh water Neogene and Quaternary strata. Part of the basin fill is the Upper Miocene-Pliocene Domański Wierch series. Within the series, clasts (up to 1.3 m across) are commonly fractured. In particular exposures, these fractures occur as a single set of extensional joints or as two sets of shear fractures conjugated under small dihedral angle. The fractures were formed due to regional stress field with the maximum stress axis (δ1) horizontal and trending NE to NNE.It follows from the analysis of tectonic deformation in the Orawa Basin substratum, that a similarly oriented stress field occurred in the discussed area during Middle Miocene time. Moreover, results of breakout analysis in the area indicate that similarly oriented stress field occurs there at Present. It is concluded therefore, that the stress arrangement within the Orawa Basin region has not undergone significant rotations, since Middle Miocene times. This stress arrangement has been characterized by horizontal δ1 trending NE to NNE.