The existence of a fault zone near the town of Paks has been suggested by several studies (Szilard 1955; Ronai 1973; Nemedi Varga 1977; Korossy 1982; Pogacsas et al. 1989; Kokai and Pogacsas 1991) since the first indication on the structural map of Loczy Jr. (1939). These studies, based on different geologic data and concepts, arrived at the same conclusion; there is an approximately SW-NE trending regional fault zone which crosses the river Danube in the vicinity of Paks, where the Hungarian Nuclear Power Plant (NPP) is located. Ronai (1973) described this zone as a primary lineament of Quaternary tectonism, while Pogacsas et al. (1989) characterized it as a Pliocene-Quaternary strike-slip fault. More than ten years of intensive research supported by the Paks NPP verified and mapped in detail this fault zone of Middle Miocene age. However, no consensus has been reached in the question of fault reactivation during recent times. Balla et al. (1997) claim that there is no evidence of Quaternary fault activity, but our studies contradict this opinion. Seismic profiling carried out on the river Danube imaged faulted Pliocene strata (Torony Formation), but no tectonic deformation could be observed in the unconformably overlying latest Quaternary (0 to 50 ky) fluvial beds. This remarkable time gap between the Torony Formation and the alluvium of the river Danube in the Paks study area is the reason why the exact time period of fault reactivation may be the subject of debate. A more favorable situation can be found, however, around and below the Tisza River in the middle and southern part of the Great Hungarian Plain. Here the Pliocene-Pleistocene strata are apparently complete and their contact is conformable. A long seismic profile acquired in 1996 on the river Tisza documents late Pleistocene (310 ky) fault activity at the Martfu bend of the river. The structural connection between the two fault segments imaged below the rivers Tisza and Danube, at Martfu and Paks respectively, has been documented by Pogascas et al. (1989) using petroleum industry seismic sections and borehole data. Accordingly, it is concluded that Quaternary reactivation of the fault zone passing by Paks cannot be questioned.
|Number of pages||20|
|Journal||Acta Geologica Hungarica|
|Publication status||Published - Dec 1 1999|
- High resolution seismic
- Quaternary tectonics
- Structural analysis
ASJC Scopus subject areas