An InSAR Deformation Phase Retrieval Method Combined with Reference Phase in Mining Areas

Abstract

The acquisition of precise deformation data, including the entirety of the subsidence basin resulting from subterranean mining operations, assumes critical significance in the context of surface impairment monitoring during the course of mining activities. In light of the constraints associated with InSAR technology when applied to the surveillance of expansive deformation gradient mining regions, an innovative approach is advanced herein for InSAR deformation phase retrieval. This approach integrates a reference phase, derivable through a variety of means, including pre-existing models or measurements. Initially, the reference deformation phase is subjected to subtraction from the wrapped InSAR deformation phase, culminating in the derivation of the wrapped phase indicative of the residual phase. Notably, it is posited that the fringe density characterizing the wrapped phase of the residual phase is theoretically diminished in comparison to that of the InSAR wrapped phase. This reduction in complexity in phase unwrapping ensues as a direct consequence. Subsequent to this, the phase retrieval process is effectuated through the summation of the reference phase and the unwrapped phase pertaining to the residual phase. The study harnesses Sentinel-1A and ALOS PALSAR-2 data, employing the PIM-predicted outcomes and GNSS-RTK monitoring outcomes as reference phases for the execution of phase retrieval experiments in two designated study areas. The computation of subsidence is subsequently realized through the combination of the displacement vector depression angle model and the retrieved phase, with the accuracy thereof corroborated through the utilization of leveling data. The experimental findings underscore the efficacy of the reference phase retrieval methodology in securing a more precise deformation phase characterization within expansive deformation gradient mining regions, thereby demonstrating the suitability of this methodological approach.

Application of the Time Function Model for Dynamic Deformation Prediction in Mining Areas under Characteristic Constraints

“…The LOS azimuth angle, α LOS , is 83.9 movement of point 16 was 0.068 m and its horizontal movement was 0.07 m. In compari-son, point 31 exhibited vertical and horizontal deformations of 0.141 m and 0.02 m, respectively, while for point 33 these values were 0.141 m and 0.021 m, as detailed in Table 2. The spatial relationship among the horizontal displacement vector horizontal d (i.e., the deformation along the strike line), the vertical deformation vector vertical d , and the LOS of the Sentinel-1 are shown in Figure 6 and can also be represented by Equation ( 18) [38]. 18).…”