Abstract
In view of a possible seismic gap in the western part of the North Anatolian Fault Zone, we carried out electric and magnetic observations in the Iznik-Mekece area, aiming primarily at searching for location of an active fault and disclosing an anomalous structure associated with it. For reference, we also made similar observations at the Ismetpasa area where an earthquake of magnitude 7.6 took place in 1944 and fault lines are well known. The preliminary results of observations are summarized as follows: in most cases, magnetic anomalies are found along fault lines, and the ground resistivity tends to be lower near fault lines. Comparison of these anomalous features in both the observation areas indicates that the active fault found in the Iznik-Mekece area is similar to the fault in the Ismetpasa area. It is suggested, therefore, that the fault in the Iznik-Mekece area may be one of the candidates for future earthquake generation in the seismic gap region.