Observation and analysis of low-frequency crustal earthquakes in Lake Van and its vicinity, eastern Turkey

Lake Van is located in very intensely deformed tectonic settings in the eastern Turkey. The surrounding area of Lake Van has major tectonic structures; NE and NW trending active conjugate strike-slip faults, pull-apart basins along these faults, E-W trending active thrust faults, folds, compressional ramp basins, N-S trending folds, NE-SW aligned continental collision-related volcanoes and N-S trending tensional cracks functioned as magma conduits. Since the area is tectonically very active, the earthquake activity within the basin and the surrounding area of Lake Van is very high. In this study, we have analysed the records of VANB broadband station of Kandilli Observatory and Earthquake Research Institute's network for the seismic events (2000-2004) that occurred in the basin and in the vicinity of Lake Van. Based on the spectral analysis of earthquake data, we have mainly observed three types of seismic events; hybrid event, long period event and tremor. We have suggested that the observed hybrid, long period and tremor type of seismic events that occurred in the study area are related to the upward moving materials and stress loading in the mid and lower crust based on the geophysical data.