Abstract

The aim of this study determined spatial-temporal variations of Gutenberg-Richter b-values using the Classic Method of Moment (CMM) and seismicity in and around Lake Van. We wrote a Matlab program for this method in the Matlab system. The faults for the Van region used as updated in the GIS system given the reference from the different sources by Bayrak and Türker (will be used in the doctoral thesis). Around Lake Van divided into 4 different seismic source regions. For each seismic source region, probabilities ranging from 0 to 1, the annual probability of exceedances and return periods were calculated for the next 25, 50 and 100 years. Van region determined the seismicity b value changes, β-values. We mapped spatial variations of the b-values using the GIS system. As a result, Lake Van region (region 2) occurred 7.1 magnitude an earthquake in the next 100 years with 31 % probability levels. If it occurred in the 50 years with 15 % probability levels, in the 25 years with 7.8 % probability levels. We estimated the low b-values in the Lake Van so, it has been the high seismicity and can be occurred an earthquake as the high magnitude in the next years. This study will be lead to earthquake hazard analysis and seismic hazard studies in and around Lake Van.

References

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