Coseismic and Postseismic Slip Analysis of the 2024 <italic>M</italic>w 7.0 Wushi Earthquake: Insights From InSAR Observations and Slip Inversion

• الحاوية / القاعدة: IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing
• المؤلفون الرئيسيون: Jianlong Chen, Zicheng Huang, Lejun Lu, Peizhen Zhang
• التنسيق: مقال
• اللغة: الإنجليزية
• منشور في: IEEE 2025-01-01
• الموضوعات: 2024 Wushi earthquake; coseismic slip; coulomb stress; frictional properties; interferometric synthetic aperture radar (InSAR); postseismic deformation
• الوصول للمادة أونلاين: https://ieeexplore.ieee.org/document/11141694/
• تدمد: 1939-1404; 2151-1535

Analysis of fault slip behavior is crucial for assessing regional seismic hazards. This study employs Sentinel-1 SAR data to investigate the coseismic and postseismic deformation associated with the 2024 <italic>M</italic>w 7.0 Wushi earthquake using Interferometric Synthetic Aperture Radar (InSAR) technique. Through multitemporal InSAR analysis, we reconstructed the coseismic slip distribution and revealed the spatiotemporal evolution of postseismic slip. The coseismic rupture released a seismic moment of 3.65<inline-formula><tex-math notation="LaTeX">$\times 10^{19}$</tex-math></inline-formula> N <inline-formula><tex-math notation="LaTeX">$\cdot$</tex-math></inline-formula> m (<italic>M</italic>w 7.0) with maximum slip of 2.3 m at 12 km depth. Coseismic Coulomb stress changes triggered the <italic>M</italic> 5.6 aftershock on January 30, 2024, with surface rupture observed. Postseismic deformation exhibits coupled afterslip&#x2013;aftershock mechanisms, showing asymmetric line of sight (LOS) displacement with maximum uplift of <inline-formula><tex-math notation="LaTeX">$\sim$</tex-math></inline-formula>20 cm (ascending track) and <inline-formula><tex-math notation="LaTeX">$\sim$</tex-math></inline-formula>15 cm subsidence superimposed on 20 cm uplift (descending track). Time-series analysis reveals a two-phase decay pattern: rapid deformation at 20 cm/month during the initial two weeks, decaying to 0.5 cm/month over subsequent four months. The friction parameter (0.001 <inline-formula><tex-math notation="LaTeX">$&lt; $</tex-math></inline-formula> <inline-formula><tex-math notation="LaTeX">$a - b$</tex-math></inline-formula> <inline-formula><tex-math notation="LaTeX">$&lt; $</tex-math></inline-formula> 0.003) indicates velocity-strengthening behavior in the Maidan fault&#x2019;s postseismic slip zone, suggesting stable slip characteristics. However, the relatively low friction coefficient still warrants attention to long-term fault motion and strain accumulation. This study provides new observational constraints for understanding postseismic deformation mechanisms and frictional properties in the South Tianshan orogenic belt.