The earthquake of 12 April 1998 in the Krn Mountains (Upper Soča valley, Slovenia) and its seismotectonic characteristics
AbstractThe earthquake on 12 April 1998 at 10h 55min UTC (12h 55min local daylight-saving time) in the Krn mountains was according to its magnitude (mb=5.3, Mm =5.3, MLV=5.6, MW=5.6, MS=5.7, MWA=6.0) among the strongest in Slovenia in the 20th century. Its epicentre was situated about 8 km south-east from the town of Bovec and its hypocentral depth was 7.6 km. The maximum intensity VII-VIII EMS-98 was observed in four villages. Mainly older buildings, built of rubble and simple stone, were damaged. A temporary network of portable stations deployed immediately after the earthquake has recorded more than 7000 aftershocks. From the earthquake mechanism and the distribution of the aftershock foci, we conclude that the main shock has happened on the dextral strike-slip subvertical fault striking NW-SE. The fault rupture dimensions were approximately 10 km x 7 km; however, no evidence of a surface rupture was found. The seismotectonic analysis of the region is based on the field observations and analysis of aerial photographs, the distribution of aftershocks and the depth distribution of focal mechanisms. These data reveal that recent tectonic activity in western Slovenia is connected to strike-slip faults in NW-SE direction as well as to thrusting along the Southalpine thrust front and parallel thrust planes.
How to Cite
Zupančič, P., Cecić, I., Gosar, A., Placer, L., Poljak, M., & Živčić, M. (2001). The earthquake of 12 April 1998 in the Krn Mountains (Upper Soča valley, Slovenia) and its seismotectonic characteristics . Geologija, 44(1), 169–192. https://doi.org/10.5474/geologija.2001.012