| Abstract [eng] |
Author: PhD. student of Nature Research Centre Andrius Pačėsa. The East Baltic Region (EBR) is notable for low seismic activity. Nevertheless, couple dozens of earthquakes with intensity up to VII (MSK-64 scale) have been recorded since 1616 to the current times. Moreover, instrumentally recorded earthquakes in Osmussaar island in Estonia of magnitude M=4.7 in 1976 and in Russian Kaliningrad enclave (M=5.0 and M=5.2) in 2004 showed that earthquakes in the EBR has to be considered seriously. Furthermore, earthquakes originated in the distant (~1300 km) Vrancea (Romania) seismogenic zone (SZ) are inducing perceptible trembling in the EBR 3-4 times per century on average. A few trials to evaluate seismic hazard of the EBR have been made in the past using somehow outdated Deterministic Seismic Hazard Assessment (DSHA) method or more modern Probabilistic Seismic Hazard Assessment (PSHA) methodology covering just some parts of the EBR. Therefore, a new seismic hazard evaluation of the EBR based on PSHA methodology was carried out in this study. Five PGA (Peak Ground Acceleration) maps corresponding to different exceedances of probabilities were compiled in this study. It was found that the Vrancea SZ induced more significant influence to seismic hazard of the EBR then exceedance of probabilities were higher (10E-2, 10E-3 per year) and the local EBR SZ were dominating then exceedance of probabilities were lower (10E-4, 10E-5 per year). |
