Multi-technique SAR coseismic deformation retrieval and fault modeling of the 2025 Mw 7.7 Myanmar earthquake

Abstract This study investigates the coseismic displacement field caused by the Mw 7.7 earthquake that struck Myanmar on March 28, 2025, along a segment of the Sagaing Fault, a well-known, right-lateral strike-slip fault. To such a purpose, a combination of satellite synthetic aperture radar (SAR)-based techniques, specifically Pixel Offset Tracking (POT), Multiple Aperture Interferometry (MAI), and SAR interferometry (InSAR), was applied to multiple Sentinel-1 SAR images covering the broad region affected by the seismic event. The retrieved deformation measurements were subsequently inverted using an analytical model to reconstruct the geometry and key parameters of the seismogenic source. In addition, a Coulomb Failure Function (CFF) analysis was performed to assess the stress transfer from the mainshock to the Mw 6.7 aftershock and determine the positive correlation between the two subsequent events. The results revealed a rupture extending approximately 490 km across three distinct fault segments, with a nearly vertical, north–south orientation and predominantly right-lateral strike-slip mechanism, in agreement with the regional tectonic setting. This comprehensive analysis offers key insights into the rupture extent and the mechanics of the major seismic event.