Tertiary deformation history from seismic section study and fault analysis in a former European Tethyan margin (the Mecsek-Villany area, SW Hungary)

摘要

Outcrop-scale structural data and seismic section interpretation are combined to unveil a very complicated Tertiary deformation history of a once Tethyan margin: the Mecsek-Villany area of Hungary. This combination of data helped to reconstruct the possible activity of individual fault zones. At least four ENE-WSW striking zones-the Northern Imbricates, the South Mecsek zone, the Gorcsony-Mariakemend ridge and the Villany Mountains-were confirmed as regional long-lived transpressive zones with very complicated internal deformation, frequently with oppositely dipping thrust faults. Tertiary structural history began with a roughly N-S-directed shortening in the South Mecsek zone. It was followed by a NE-SW-directed transpression activating practically all important wrench zones together with perpendicular transfer faults. Basins were created along some of these deformation zones, but were also affected by major tilts due to inversion. After a relatively quiescent period in the Middle Miocene, the Late Sarmatian inversion followed. Shortly after, this event was relayed by a NE-SW-directed extension-transtension. An important inversion period characterised by NW-SE compression occurred in Late Pannonian (Messinian), when all the former wrench zones were reactivated as right-lateral shear. This event is responsible for the present topography of the region. (C) 2002 Elsevier Science B.V. All rights reserved. [References: 41]