A novel method combining advanced radar technology and probabilistic modeling has emerged as a significant breakthrough for monitoring three-dimensional surface deformation within mining areas. This innovative approach, integrating SBAS-InSAR (Small Baseline Subset Interferometric Synthetic Aperture Radar) and the Probability Integral Method (PIM), aims to address the challenges posed by surface subsidence caused by mining activities, especially in regions where vegetation hinders traditional monitoring methods.
Mining activities, particularly coal extraction, can lead to severe geological issues such as ground subsidence, which may pose risks to both infrastructure and local communities. The extraction process generates voids underground, resulting in the ground above becoming unstable and susceptible to collapse or related disasters. Therefore, reliable monitoring of subsidence is imperative for ensuring safety and maintaining the integrity of surface structures.
Traditional monitoring practices, such as intensive leveling and Global Navigation Satellite System (GNSS) measurements, have often proven laborious and limited. While Interferometric Synthetic Aperture Radar (SAR) technology has revolutionized the efficiency of surface deformation monitoring, limitations remain—especially with regards to measuring deformations outside of the line of sight or under areas burdened with dense vegetation.
To overcome these challenges, researchers have developed the SBAS-PIM method, which synergistically utilizes data from high-coherence points alongside GNSS data to accurately calculate three-dimensional surface deformations. This advancement minimizes the required number of measurements and significantly reduces associated labor costs. The integration of PIM allows for the modeling of deformation across multiple working faces and provides reliable data even where traditional methods fall short.
Recent applications of this method at a mining site located in Heze City, Shandong Province, China, involved the analysis of 82 Sentinel-1 A images to assess land movement accurately. Remarkably, the research documented maximum vertical displacement of -2011 mm, alongside notable east-west and north-south movements, signaling impressive results for deformation monitoring.
Further validation through GNSS data demonstrated high reliability of the SBAS-PIM method, with correlation coefficients exceeding 0.9 for the vertical and east-west displacement directions. These findings confirm the method's practical applicability, proving it capable of effectively addressing the complex surface deformation dynamics present within mining environments.
While the SBAS-PIM technique presents substantial advancements for monitoring surface movement, it is important to acknowledge existing gaps—particularly with regards to north-south displacement measures, which currently exhibit notable discrepancies. Continued experimentation and refinement may be required to bolster the method's overall precision and versatility.
Overall, the deployment of the SBAS-PIM method heralds significant progress toward improving monitoring practices within mining regions, allowing for enhanced safety measures and potentially transforming how we approach subsurface deformation assessment. Ongoing research and application of this technology may pave the way for safer and more sustainable mining practices in the future.