Observation of seismicity based on DOMERAPI and BMKG seismic networks: A preliminary result from DOMERAPI project

DOMERAPI project has involved earth scientists from Indonesia and France to conduct comprehensively a study of the internal structure of Mt. Merapi and its vicinity based on seismic tomographic imaging. The DOMERAPI seismic network was running from October 2013 to April 2015 consisting of 53 broad-band seismometers, covering Mt. Merapi and Mt. Merbabu, and some geological features such as Opak and Dengkeng faults. Earthquake hypocenter determination conducted in this study is an important step before seismic tomographic imaging. The earthquake events were identified and picked manually and carefully. The majority of earthquakes occured outside the DOMERAPI network. The ray paths of seismic waves from these earthquakes passed through the deep part of the study area around Merapi. The joint data of BMKG and DOMERAPI networks can minimize the azimuthal gap, which is often used to obtain an indication of the reliability of the epicentral solution. Our preliminary results show 279 events from October 2013 to m...