Recently, several books on the geology of Hungary have reviewed the stratigraphy and structural evolution of the different megatectonic units using the principle of evolutionary cycles. The Transdanubian Range Unit (TRU) is considered by some authors to be exceptional, because in this unit a complicated Late Cretaceous to Eocene stratigraphy is associated with a simple structure. Namely, the unit bordered by two boundary faults (the Rába and Balaton Lines) is supposed to have been affected only by block-faulting during the Eo-Alpine orogeny. In this paper the authors reiterate a counter-opinion which they first expressed more than 15 years ago. Based primarily on the interpretation of data from more than 150 hydrocarbon exploration wells and 2000 km of seismic lines. It is argued that the TRU is actually characterized by a nappe structure and situated at the top of the Austroalpine nappe pile, as envisaged by UHLIG (1907) more than a century ago. It is also suggested that the seismically- mapped thrust planes at the fully sedimentary-covered north-western flank can be tied to the traditionally recognised thrust faults on the exposed south-eastern flank of the TRU. This leads to a straightforward allochthonous model and provides an inference about the original (Late Cretaceous to Eocene) continuity of the Transdanubian Range and the Northern Calcareous Alps. Finally, the paper argues that the complex Late Cretaceous stratigraphy of the TRU has been controlled by the development of flexural basins and highs in front of the advancing nappe systems.
|Number of pages||28|
|Publication status||Published - Dec 27 2010|
ASJC Scopus subject areas
- Geochemistry and Petrology