Správa o zemetrasení pri Banskej Bystrici 6. apríla 2022

We present seismological and geological interpretations of the weak earthquake that occurred on April 6th, 2022 with epicenter between Šalková (suburb of Banská Bystrica) and Slovenská Ľupča. The local magnitude of the event was ML = 2.1. The earthquake was macroseismically observed in 21 localities (101 reports) on the territory of Slovakia with epicentral intensity 4° EMS-98. The estimated focal mechanism indicates a normal fault in approximately E-W direction. This favours the theory of an extension regime in the Čertovica tectonic zone

Carpathian Shear Corridor – A strike-slip boundary of an extruded crustal segment

The Carpathian Shear Corridor (CSC), a morphostructurally distinctive ENE-WSW brittle shear zone, is a prominent dynamic interface of crustal fragments shifted during an oblique collision process combined with lateral extrusions in the Late stages of the Western Carpathians tectonic evolution. This tectonics was due to convection in the upper mantle, driven mainly by slab-pull forces related to a subductional process in front of prograding Carpathians. The CSC separates the marginal segment of the Western Carpathians, already firmly attached to the European plate, from the southern still eastwardly moving block. This process led to structural transpositions, anomalous rotation of small blocks and tilting and uplift/subsidence events, resulting in a tectonic style of horst and intramountaine basin alternations within the corridor. Preliminary paleomagnetic data indicate anomalous CCW block rotations within this corridor, and AFT ages indicate Early and Late Miocene (ca 24–22 Ma and ca 10–7 Ma) fault controlled exhumation events triggered by increased shear zone activity. Deep seismic sections, magnetotelluric and gravity data show that CSC follows a frontal ramp of the Western Carpathians thrust over the foreland. The CSC remains an active strike-slip shear zone, and therefore the most important earthquake risk-zone in the Slovakian portion of the Western Carpathians. It presents a lateral ramp transform boundary of eastwardly extruding crustal segment during the Miocene and up to the recent time