五龙沟矿区时序InSAR地表形变监测

Time series InSAR surface deformation monitoring in Wulonggou mining area

矿区资源开采引发的环境地质问题日益突出,地表形变监测可对矿业开采沉降进行有效预估,最大限度地降低地表沉降带来的损失。五龙沟矿区作为青海省重要的矿产地之一,对其进行形变监测具有重要意义。传统D-InSAR技术易受时空去相干和大气相位延迟限制,导致形变监测失效,而SBAS-InSAR技术则能突破上述限制条件,获得毫米级的地表形变特征。因此,本文选取覆盖该区域的2017—2019年30期Sentinel-1A降轨数据,采用时序InSAR技术对该矿区进行地表形变监测,最后从整体形变、形变速率、形变量等方面进行时序分析。实验结果表明:矿区的整体形变不大,其平均沉降速率为-1.40 mm/a,最大年平均沉降速率为-11.8 mm/a,最大形变量为-21.7 mm。矿区范围内存在两个主沉降区,其中沉降区A呈漏斗状,沉降区B呈条带状,随着时间的推移均有明显向外扩张趋势。监测结果可为矿区后期防护治理与安全生产提供参考资料。

The environmental geological problems in mining areas caused by resource mining are becoming increasingly prominent.Surface deformation monitoring can effectively predict mining subsidence and minimize the losses caused by surface subsidence.As one of the important minerals in Qinghai province,Wulonggou mining area is of great significance for deformation monitoring.The traditional D-InSAR technology is vulnerable to the temporal and spatial coherence and atmospheric phase delay,resulting in deformation monitoring failure,while the SBS-InSAR technology can break through the above limitations and obtain the surface deformation characteristics of millimeter-scale.In this paper,Sentinel-1A landing data of 30 images covering the area from 2017 to 2019 are selected to monitor the surface deformation of the mining area by using time-series InSAR technology.Finally,the time series analysis is carried out from the aspects of overall deformation,deformation rate,and settlement.The results show that the overall deformation of the mining area is not obvious,the average settlement rate is-1.40 mm/a,the maximum annual average settlement rate is-11.8 mm/a,and the maximum deformation is-21.7 mm.There are two main settlement areas in the mining area,of which settlement area A is funnel-shaped and settlement area B is strip-shaped,both of them have a tendency to expand with the passage of time.The monitoring results can provide reference materials for the protection and management of the mining area in the later period and production safety.