Geophysical Research Abstracts, Vol. 7, 06945, 2005 SRef-ID: 1607-7962/gra/EGU05-A-06945 © European Geosciences Union 2005 Miocene tectonics along the Mid-Hungarian fault zone - implications from northern Romania B. Fügenschuh, M. Tischler, H.R. Gröger, S. Schmid, and A. Wetzel Institute of Geology and Paleontology, University of Basel, Basel, Switzerland The Tertiary emplacement of the continental Alcapa and Tisza–Dacia blocks into the Carpathian “embayment” is a key issue for understanding the evolution of the Carpathian orogen (Csontos & Vörös, 2004). The Mid Hungarian fault zone, sepa- rating these two blocks (Csontos & Nagymarosy 1998), is for the most part covered by sediments of the Pannonian basin, and can only be studied by geophysical data in most places. Alcapa has been thrusted over Tisza – Dacia during Late Oligocene to Early Miocene times along an individual fault named "Mid Hungarian line" (Csontos & Nagymarosy 1998), a part the broader deformation belt of the Mid-Hungarian fault zone. Our field-studies in northern Romania provide kinematic, sedimentological and fission track data for northern Romania, where parts of the Mid Hungarian fault zone are outcropping. The non-metamorphic flysch units of the Pienides represent the easternmost parts of the outer west Carpathians (Plasienka 1997), and were emplaced onto the Pale- ocene to lower Miocene post-tectonic cover of the Bucovinian nappes in Burdigalian times. During Oligocene to Aquitanian times flysch sedimentation prevails in the au- tochtononous domain, exhibiting an overall coarsening-up trend, finally resulting in the deposition of Burdigalian-age molasses deposits. These deposits show a wedge- shaped geometry, as imaged by seismic sections from the northern Transylvanian basin. (Ciulavu et al 2002 and references therein). Later left-lateral movements along the Bogdan-Dragos Voda fault, which is part of the eastern Mid Hungarian fault zone, offset these early Miocene thrust contacts. The Burdigalian-age emplacement of the Pienides is dominated by consistently SE- directed thrusting under brittle conditions while folding is of subordinate importance. The curved map appearance of the thrust contact is due to lateral ramps and tear faults,