부산대학교 도서관

The transition zone between the subsiding western Pannonian Basin and the uplifting Eastern Alps is a slightly undulating hilly realm, consisting of large plateaus, pediment surfaces and locally steep scarps. These rectilinear slopes are considered as being controlled by structural elements as suggested by the digital elevation model (DEM), although a simple denudation origin cannot be ruled out from surface data only. One of the steep slopes, the Torony scarp is situated E from the Eisenberg-Vas Hill and was investigated with diverse methods: 2D electric tomography, 1D electric resistivity data, correlation of borehole data and fault-slip analysis. The dense network of shallow boreholes and the applied geophysical methods constraints well the structural geometry of the Upper Miocene (Pannonian) lignite layers. While Miocene layers were only very slightly tilted away from the Torony scarp, they are faulted and folded just below the scarp. Correlation of layers on both sides of the scarp is not unequivocal, thus the exact total vertical displacement can only be estimated between 25-50 meters. Observations are in agreement with the assumptions based on the DEM: the Torony segment of the Arany creek is controlled by a fault system. The fault system is composed of two sets: a NE-SW and one (W)NW-(E)SE striking. The former can be interpreted as en echelon faults, while the latter set as connecting fault splays between the main en echelon segments. Outcrop-scale observations revealed partly syn-sedimentary Late Miocene and partly younger normal faulting. Based on the age of the underlying sedimentary units the Torony fault system could not start earlier than 8.7 Ma, most probably at 8.3 Ma. On the other hand, the deformation partly post-dates the Late Miocene layers. Depending on correlation of lignite strata across the fault zone and on the concept on the denudation process, the post-sedimentary part of faulting could be pre-Quaternary or Quaternary. Presence of active mass movements and deeply eroded gullies suggest that the slope is still unstable; this may be an indirect indication of fault-controlled slope development. The Torony fault is part of a system of Late Miocene or younger faults which partly reactivated, partly dissected the earlier syn-rift (late Early to Mid-Miocene) faults of the western Pannonian Basin. Besides the structural results, this paper emphasizes the advantage and necessity of simultaneous usage of geophysical measurements, field observations, morphological investigations and borehole data. [ABSTRACT FROM AUTHOR]