Overview of the pre-Neogene basement collage of the Pannonian Basin

The extensional Neogene Pannonian Superbasin was superimposed on an Alpine, Cretaceous-Paleogene compressional realm which left a significant structural footprint in the pre-rift basement. Even though the surrounding Eastern Alps, Carpathians, and Dinarides project below the Pannonian Basin, even the existence of Alpine thrust-fold belts, including large nappes in the pre-rift basement of the Pannonian Basin has been debated until just a few decades ago. Based on the interpretation of primarily subsurface data sets, such as academic and industry reflection seismic and borehole data, the Cretaceous structural units of the Eastern Alps are correlated beneath the northwest Pannonian Basin with corresponding tectonic units of the Western Carpathians. Similarly, the Alpine folded belt beneath the southeast Pannonian Basin has a structural style very similar to the internal part of the Eastern and Southern Carpathians, specifically that of the Apuseni Mts. However, the level of understanding of the Eo- and Meso-Alpine thrust-fold belts beneath the Pannonian Basin system remains rudimentary compared to those known in the surrounding classical regions of the Eastern Alps, Carpathians and Dinarides. This mismatch is primarily caused by the subsurface nature of the problem and the pronounced overprint by Neogene transtensional tectonics.