Author(s)

C. Mekik, H. Kutoğlu & K. S. Gormus

Abstract

North Anatolian Fault (NAF) is the largest and longest earthquake producing fault of Turkey which extends from its Iranian border in the east to Marmara Sea in the west with a length of 1200km. It separates the Eurasian Plate and the Anatolian Plate and has similar features to the San Andreas Fault in California in USA in that both faults have a right-lateral strike slip faulting mechanism, similar lengths and linearity as far as their poles of rotation are concerned. NAF is considered to be one of the longest and most active fault systems in the world, and thus has been the stage of 11 major earthquakes (Mw >6.7) since 1939. Two of these major earthquakes occurred in the Ismetpasa segment of the fault, located 350 km east of Istanbul at the intersection of Karabuk and Cankiri provinces in north-central Anatolia, the Asia Minor, and 100km north of Ankara, the capital of Turkey. The Ismetpasa segment of NAF stands out with its aseismic fault slip feature, also referred to as creeping, as the rare occurrence in the world. The Ismetpasa first drew attention by a gradually enlarging crack on the wall of State Highway Maintenance Station built in 1957 and its aseismic slip movement that caused an offset in the wall was first reported in 1969 by Ambraseys. Since then, many researchers have investigated the creep by conducting various measurement methods from conventional surveying techniques to modern techniques such as GPS, LIDAR, InSAR. This paper documents the studies carried on NAF at Ismetpasa segment in a chronological perspective, and also gives the latest findings obtained by different research groups in the last decade. Keywords: North Anatolian Fault, Ismetpasa segment, fault creep, geodetic measurements.

Keywords

North Anatolian Fault, Ismetpasa segment, fault creep, geodetic measurements