Unraveling the Rupture Properties of Four Destructive Earthquakes in Türkiye (1966‑1975)

Abstract

This study presents finite‑fault rupture models for four destructive earthquakes in Türkiye: the 1966 Varto (MW = 6.7), 1967 Mudurnu Valley (MW = 7.3), 1971 Bingöl (MW = 6.7), and 1975 Lice (MW = 6.6) events. Using a teleseismic waveform inversion technique, we derive the spatial distribution of slip, rupture geometry, and seismic moment for each earthquake. Our models reveal that the ruptures are characterized by distinct asperities and are significantly influenced by geometric fault complexities such as bends and step‑overs. The 1966 Varto earthquake involved oblique faulting with three asperities. The 1967 Mudurnu Valley rupture is dominated by a large asperity, with propagation affected by a 20‑degree fault bend. The 1971 Bingöl earthquake model supports the segmentation of the East Anatolian Fault Zone at the Göynük Bend and suggests further sub‑segmentation of the Ilıca Fault Segment at a geometric discontinuity corresponding to the northeastern edge of a large asperity. The 1975 Lice earthquake model shows rupture arrest at a western fault step‑over. These results underscore the critical role of structural discontinuities in controlling rupture initiation, propagation, and termination, providing essential insights for seismic hazard assessment in these tectonically active regions.