Proceedings of the 12th International INQUA meeting on paleoseismology, active tectonic and archaeoseismology

172 PATA Days 2024 The differences between proposed Pliocene and the current drainage pattern were analysed in relation to the results of the tectonic analysis (see Fig. 5). It was suggested that uneven uplift of foothils of Novohradské hory Mts. (namely the parts of Poluška, Slepičí hory and Lišov Horst) has led to multiple stream capturing and changes in stream direction. It is probable, that the stream of the Malše River has migrated to the E. The trunk stream of the NE part of the study area („PaleoStropnice“) could have used the valley of the present lower Svinenský stream and had an upper part similar to the present-day Stropnice River. On the basis of the mutual morphostratigraphic position of Pliocene and Pleistocene fluvial deposits, it appears that the distinct changes of the river geometry induced by tectonics may be younger (probably the lowest Pleistocene) than previously assumed. Further research and analysis is necessary for complete solving the exact timing and succession of tectonic movements along the faults and connected changes in fluvial geomorphology. It is essential to provide some dating (preferably by using of cosmogenic nuclides) of the fluvial deposits through the study area to get an absolute time dating and not only the morphostratigraphical position of the deposits, which can by locally uncertain. However, study itself provides Fig. 4: Comparing the KSG, Pliocene terraces (1-5) and Pleistocene terraces (Donau-Holocene) of the Malše River, according to Novák (1983). a solid base for subsequent research: it is possible to pinpoint important localities, where cosmogenic nuclides dating of the deposits can be done. C O N C L U S I O N S The integration of morphotectonic analysis, SL index calculation, airborne geophysical measurements, and validation with field data of structural geology and sedimentology is a powerful tool for understanding Quaternary-Neogene active tectonics in intraplate areas with low deformation rates. It is assumed there is a possible reactivation of individual faults under the recent stress-field (S Hmax = 146°). If S Hmax is horizontal in the ~NNW–SSE direction, the prevailing ~NE(NNE)–SW(SSW) trending faults would mostly reveal a sinistral strike- slip to weak reverse oblique-slip movement. A second set of subvertical ~NW(WNW)– SE(ESE) faults could be predominantly reactivated in a dextral strike-slip regime or as gentle reverse oblique-slip faults. The minor steeply dipping faults perpendicular to the S Hmax = 146° are not active. Based on these results it is assumed that the whole region of the Novohradské hory Mountains experienced a significant uplift, compared to the neighboring areas