Preliminary Observations and Assessment of ？anakkale-Ayvac？k Earthquake Activity

A project was begun to monitor earthquake activity at the southwest branch of the Biga Peninsula in Ayvac？k and close surroundings beginning on 14 January 2017 with Mw=4.6 and continuing through 6 February 2017 with Mw=5.5 (Mw=5.5 Kandilli Observatory and Earthquake Research Institute – KOERI - , Mw=5.3 AFAD, Mw=5.4 ？OMü). The region has active seismicity and includes portions of the significant tectonic elements of the northwest Aegean region. Due to the continuation of earthquake activity, in addition to permanent stations linked to the national networks (KOERI and AFAD) in the region 10 continuous-form recording 3-component temporary stations were set up with the aim of observation for at least 1 year. The distances between these stations varied from 6 to 12 km. In addition to the intensity and continuity of microearthquake activity in the region, and the inclusion of geothermal fields in the region, the necessity to investigate the seismotectonic character of the region in detail came to the agenda. Together with permanent stations belonging to national observatories in the study area, the station density was insufficient to reveal these details. As a result, data from both national network and temporary stations will contribute to understanding the tectonic character of the region. When temporary stations at close proximity to the main shock and epicenter distribution are compared with the national network primary results indicate there were significant improvements in identifying microearthquakes especially and in determining their locations. Additionally, and in source mechanism solutions belonging to earthquake data with moderate magnitude, faulting with a dominantly NW-SE oriented normal offset component was observed. This study aims to reveal the time and spatial distribution, frequency content and source mechanisms for earthquakes occurring in the southwest of the Biga Peninsula near Ayvac？k and surroundings, in addition to determining a detailed velocity model with local tomography