Surface deformations of the 6 February 2023 earthquake sequence, eastern Türkiye

Abstract

Two powerful earthquakes struck Türkiye on 6 February 2023. The initial rupture was on the Dead Sea fault zone, yet maximum displacements and energy release [moment magnitude ( M _w ) 7.8] occurred 24 seconds later when rupture transferred to the East Anatolian fault zone (EAFZ). More than 7 hours later, a M _w 4.5 aftershock at the junction of the EAFZ with the east-west striking Çardak-Sürgü fault was followed 86 minutes later by the second large ( M _w 7.5) earthquake, suggesting a causal relationship. We provide quantitative ground and aerial documentation of surface offsets and kinematics from the slipped faults, providing important data on surface deformation during large continental strike-slip earthquakes, rupture propagation mechanisms, and how slip may be transferred between complex fault systems. We also provide insight into how slip along linked fault systems accommodates global plate motions.

Editor’s summary

The 2023 earthquake sequence in Türkiye and Syria caused a great deal of damage and loss of life. Meng et al . captured surface features with a comprehensive set of field and drone observations before these features could be eroded or destroyed. The surface deformation caused from the underlying faults was complex but provides insight into fault displacement, rupture propagation, and slip transfer between fault systems. These observations should help with future seismic hazards and with interpreting events from the historic record. Ren et al . used an array of geophysical observations to determine how rupture propagated along the complex series of faults. The rupture speed was faster than the shear wave velocity at times, a condition called supershear. The authors pieced together some of the underlying physics behind this complex earthquake, helping us better understand the rupture process and subsequent ground shaking. —Brent Grocholski

Abstract

Surface observations from the 2023 eastern Türkiye earthquake sequence provide insight into complex fault systems.