Research on Surface Subsidence Monitoring of Coal Mining Working Faces Based on LT−1 Satellite Data

To reveal the spatiotemporal evolution pattern of surface subsidence above coal mining working faces, time−series monitoring and analysis of surface subsidence at Working Face S1216 in the Ningtiaota Mining Area (March 12 to June 4, 2025) were conducted using D−InSAR technology with images acquired by the domestic LuTan−1 (LT−1) satellite. The results show that:(1) During the mining process of the working face, surface subsidence exhibits a progressive expansion trend over time. The subsidence area increases from 0.2 km² to 0.73 km², and the maximum subsidence detected by D−InSAR rises from 60 mm to 110 mm. The subsidence basin takes an elliptical shape with pronounced asymmetry along the dip direction, and the subsidence influence range on the goaf−adjacent side is significantly larger than that on the solid coal−adjacent side.(2) From March to June 2025, surface subsidence develops continuously as the working face advances. The maximum subsidence along the dip profile monitored by D−InSAR increases from −46 mm to −103 mm. Both the depth and influence scope of the subsidence basin expand notably, which verifies the applicability of LuTan−1 satellite−based D−InSAR technology for subsidence monitoring of coal mining working faces.(3) Quantitative analysis of the influence angles of the subsidence basin indicates that with the continuous advancement of the working face, the dip influence angle on the goaf side decreases from 40.17° to 27.73°, the dip influence angle on the solid coal side drops from 72.79° to 37.94°, the advance influence angle along the strike reduces from 72.2° to 68.6°, and the lag influence angle along the strike decreases from 33.4° to 13.8°.These research findings provide a reference for the application of the domestic LuTan−1 satellite in coal mining subsidence monitoring, as well as for the prevention and control of subsidence disasters in mining areas.