A RUPTURE MODEL FOR THE 1967 MUDURNU VALLEY, TURKEY EARTHQUAKE AND ITS IMPLICATION FOR SEISMOTECTONICS IN THE WESTERN PART OF THE NORTH ANATOLIAN FAULT ZONE

摘要

Six destructive earthquakes had successively occurred from 1939 to 1967 along the North Anatolian Fault Zone. The July 22, 1967 Mudurnu Valley earthquake (Ms=7.1) was the last of this series, with its western neighbour remaining as a seismic gap. Surface ruptures associated with this earthquake appeared within a broad shear zone, extending to a distance of 80 km. The generated teleseismic body waves were so complex that they were different even at stations in the same azimuth. In this study we inverted the observed teleseismic body; waves to investigate such a presumably complicated rupture process of the Mudurnu Valley earthquake. We could identify six subevents within 2 minutes with their total seismic moment amounting to 1.1 x 10(20) Nm. Although right-lateral strike-slip faulting was found to be dominant, two minor subevents had a dip-slip mechanism; one showed a reverse faulting mechanism and the other a normal faulting mechanism. [References: 14]