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This study applies transient electromagnetic method to elucidate collapse mechanisms in an abandoned gypsum mine goaf in Hunan Province, China. TEM survey lines were laid both parallel and perpendicular to the collapse axis to generate detailed two-dimensional resistivity profiles. These profiles reveal pronounced low-resistivity corridors that spatially coincide with surface fissures—thereby delineating inclined slip planes—as well as discrete high-resistivity bodies corresponding to the residual gypsum strata. By integrating these geophysical insights with historical mining records and the ML 3.4 shallow “collapse earthquake” of March 8, 2025, we construct a three-stage collapse model: (1) progressive fracturing of the goaf roof; (2) sliding and bulk subsidence of rock mass along defined discontinuities; and (3) development of a central depression framed by peripheral micro-settlements and crack networks. The resistivity profiles offer a geophysical foundation for targeted hazard assessment and remediation planning in gypsum mine goaf environments.