Numerous significant earthquakes have occurred along the North Anatolian Fault Zone (NAFZ), Türkiye’s most important fault zone. An earthquake with magnitude of Mw 6.0 occurred near the Gölyaka District of Düzce Province at 04:08 local time on November 23, 2022. According to the moment tensor solutions published by national and international seismology centers, the earthquake occurred at the northeast end of the Karadere segment within the NAFZ and was caused by a right-lateral strike-slip fault in the NW-SE direction. In this study, the differential interferometric synthetic aperture radar (InSAR) method was employed to analyze the deformation. Four Sentinel-1A complex datasets were used, two of which were ascending (2022/11/15 and 2022/11/27) and two of which were descending (2022/11/14 and 2022/11/26) pre- and postearthquake, to determine the deformation that occurred after the earthquake. In addition, surface deformation movements in both the east-west and vertical directions were calculated using these two data sets. Elastic dislocation modeling was performed by applying linear and nonlinear inversion to determine slip distribution related to the fault structure, using the displacement amount obtained from DInSAR results and data obtained from the Global Centroid Moment Tensor (GCMT) catalog. Based on the findings from the DInSAR analysis, subsidence of approximately 5 cm and eastward movement of 8 cm were detected on the northern block of the Düzce segment. This right-lateral movement corresponds to an area of approximately 105 km2 northwest of the Düzce segment. On the southern block of the Düzce segment, elevation of about 3 cm and westward movement of about 3 cm were observed. Elastic dislocation modeling shows that the observed deformation model can be explained by slip on a single planar fault for the Gölyaka-Düzce earthquake. A right-lateral strike-slip fault with northwest dip was observed, extending down to a slip-centroid depth approximately 9.2 km within the upper crust region. The elastic slip modeling in this half-space resulted in a slip of 0.35 m, Mw of 6.1, strike of 264°, dip of 66°, and rake of –165°. This study reveals that the Düzce segment was the location where the earthquake occurred, but it is also believed that the Karadere segment was impacted by this seismic event. Overall, the study provides information about the occurrence of the Gölyaka-Düzce earthquake, subsequent deformation, and the elastic fault model in half-space.
Gölyaka-Düzce, DInSAR, earthquake, elastic model, Karadere Segment
KARACA, ŞÜKRÜ ONUR; ERTEN, GÜLTEKİN; YIKMAZ, BATUĞHAN; and ÖZALP, SELİM
"DInSAR analysis and geophysical modeling of 2022 November 23 Gölyaka-Düzce Earthquake,"
Turkish Journal of Earth Sciences: Vol. 33:
2, Article 6.
Available at: https://journals.tubitak.gov.tr/earth/vol33/iss2/6