Characteristics of Tectonic Stress Field in the Source Region of the 2023 Turkey MW7.7-MW7.6 Earthquake Doublet
XIE Yike
LI Shengle
LIU Zhumei
MA Liang
LIU Xiaoli
Abstract：Based on 834 focal mechanism solutions of the 2023 MW7.7 and MW7.6 earthquakes in southeastern Turkey,this study systematically investigated the tectonic stress field in the seismic source regions and adjacent areas using the damped regional stress tensor inversion method with partitioned grid units.The results indicate that:① The optimal inversion grid size is 0.6°×0.6°.② The predominant orientation of the maximum principal stress axis shows SSW-NNE direction,while the minimum principal stress axis predominantly aligns with EES-NWW direction.Spatially,the maximum principal stress axis exhibits clockwise deflection from south to north and west to east,whereas the minimum principal stress axis demonstrates counterclockwise deflection from north to south and east to west.The stress shape factor R-value is less than 0.5.③ The stress field in the MW7.7 earthquake source region is dominated by horizontal compressive stress accompanied by significant vertical tectonic deformation,while the stress field in the MW7.6 earthquake source region exhibits strong compression combined with pronounced shear deformation.
Keywords：Turkey earthquake doubletfocal mechanism solutionstectonic stress field
Publication Date：2025-03-31
Online Publishing Date：2025-10-10(First online date of this platform, not the publication date of the document)
Pages：9( 61-69 )