Tomographic inversion and pre-stack depth migration of seismic profile KK-02 across the Krško plain

In this paper we discuss results of analyses made on two near-regional scale seismic profiles acquired in the area of Krško Nuclear Power Plant (NPP), in SE Slovenia. Geophysical and geological data were collected to improve the seismotectonic model that is aimed at the assessment of earthquake hazards. Accordingly, the identification of active faults was the main objective of seismic profiling. The program was completed in 2000 within the project "Geophysical Research in the surroundings of the Krško NPP", supported by the EU under the PHARE Program, which finalized a grid of seismic prospecting completed by locally focalized high resolution profiling to define the position of faults extending very near the surface as accurately as possible. Two near regional lines, KK-02 and KK-03 are here analysed and discussed. Furthermore, the profile KK-02 was processed with a pre-stack depth migration after an accurate tomographic velocity inversion. The interpretation of the seismic sections so obtained points out two thrust faults developed during the Late Pontian-Pliocene, revealing the N-S tectonic compression. Continuity of these faults was studied from their nucleation inside the pre-Neogene basement to the near surface.