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D. Spahić, U. Exner, M. Behm, B. Grasemann, A. Haring, H. Pretsch:
"Listric versus planar normal fault geometry: an example from the Eisenstadt-Sopron Basin (E Austria).";
International Journal of Earth Sciences, / (2010), 1 - 11.

In a gravel pit at the eastern margin of the
Eisenstadt-Sopron Basin, a satellite of Vienna Basin
(Austria), Neogene sediments are exposed in the hanging
wall of a major normal fault. The anticlinal structure and
associated conjugated secondary normal faults were previously
interpreted as a rollover anticline above a listric
normal fault. The spatial orientation and distribution of
sedimentary horizons and crosscutting faults were mapped
in detail on a laser scan of the outcrop wall. Subsequently,
in order to assess the 3D distribution and geometry of this
fault system, a series of parallel ground penetrating radar
(GPR) profiles were recorded behind the outcrop wall.
Both outcrop and GPR data were compiled in a 3D structural
model, providing the basis for a kinematic reconstruction
of the fault plane using balanced cross-section
techniques. However, the kinematic reconstruction results
in a geologically meaningless normal fault cutting downand
up-section. Additionally, no evidence for a weak layer
serving as ductile detachment horizon (i.e. salt or clay
horizon) can be identified in stratigraphic profiles. Instead,
the observed deflection of stratigraphic horizons may be
caused by a displacement gradient along a planar master
fault, with a maximum displacement in the fault centre,
decreasing towards the fault tips. Accordingly, the
observed deflection of markers in the hanging wall-and in
a nearby location in the footwall of the normal fault-is
interpreted as large-scale fault drag along a planar fault that
records a displacement gradient, instead of a rollover
anticline related to a listric fault.

Listric fault Fault drag Ground penetrating radar

http://dx.doi.org/10.1007/s00531-010-0583-5

Project Head Ewald Brückl:
ALPASS - Seismisches Monitoring der Lithosphäre und des oberen Mantels in den Alpen 2. bis incl. 4. Projektjahr