2.5-D Surface Deformation due to the 24 January 2020 Elazig, Turkey Earthquake Estimated by Multiple Sentinel-1 InSAR Data

Despite of having capability to measure surface deformation with millimeter level of accuracy, InSAR-based measurement can only provide one dimensional data. The observed InSAR LOS displacement only measure displacement toward and away from satellite sensor, thus is rather hard to be used in depicting the deformation source intuitively. Here we attempt to resolve 2.5-D coseismic surface deformation due to the 2020 Elazig (Turkey) Earthquake by using three coseismic interferometric pair of Sentinel-1 data. The 2.5-D surface deformation show a dominant westward motion with maximum displacement of 3.92 m, which is located southwest to the earthquake epicenter. Additionally, maximum ground subsidence of 0.29 m is detected at southern area of the earthquake epicenter. The estimated 2.5-D displacement is consistent with the typical surface displacement generated by sinistral strike-slip fault. Significant westward motion also indicates that the fault is characterized by left-lateral motion. To validate these findings, LOS displacement from both ascending and descending orbits were inverted for the source model of this event. The preferred source model shows two asperities with a maximum slip of 2.6 and 4.4 m, respectively, concentrated at a depth between 5 and 12 km, releasing a geodetic moment of 1.54 x 10E+19 Nm (Mw = 6.7). Primary slip mechanism of this event is left-lateral strike-slip motion confirming the finding of 2.5-D displacement analysis. © 2021 IEEE.