New geodetic constraints to reveal seismic potential of central Marmara region, Turkey

The North Anatolian Fault (NAF) is a fault zone that produced destructive earthquakes (Erzincan 1939 and 1992, Ladik 1943, Gerede 1944, Duzce 1999, Izmit 1999) in the last century. After this destructive earthquake migration, it is forecasted that the next seismic event on the NAF could be in the western part of the fault, which passes through the Marmara region. Due to the possibility of an earthquake in Istanbul, the most crowded and historical city in Turkey, researchers have increasingly paid attention to the western segment of the NAF within the Marmara Sea since the 1999 earthquakes. Many scientists from different disciplines such as geodesy, geology, geophysics, etc. have been trying to understand this phenomenon. However, it is understood from the literature that a comprehensive geodetic study is crucial to constrain the NAF segment between Istanbul and Tekirdag provinces. Therefore, we created a new network consisting of continuous GPS stations with 10-km interdistances along the shoreline, which was integrated with existing GNSS networks in the Marmara region. Data acquisition was carried out between August 2017 and February 2020. In this study, preliminary results obtained from the integration of the newly established network with the other GNSS networks are presented.