Deformation Monitoring in an Alpine Mining Area in the Tianshan Mountains Based on SBAS‐InSAR Technology

Abstract

The fragile habitat of alpine mining areas can be greatly affected by surface disturbances caused by mining activities, particularly open-pit mining activities, which greatly affect the periglacial environment. SBAS-InSAR technology enables the processing of SAR images to obtain highly accurate surface deformation information. This paper applied SBAS-InSAR technology to obtain three years of surface subsidence information based on the 89-scene Sentinel-1A SLC products, covering a mining area (tailings and active areas) in the Tianshan Mountains and its surroundings from 25th December 2017 to 2nd January 2021. The data were adopted to analyze the characteristics of deformation in the study region and the mining areas, and the subsidence accumulation was compared with field GNSS observation results to verify its accuracy. The results showed that the study area settled significantly, with a maximum settlement rate of −44.80 mm/a and a maximum uplift rate of 28.04 mm/a. The maximum settlement and accumulation of the whole study area over the three-year period were −129.39 mm and 60.49 mm, respectively. The mining area had a settlement value of over 80 mm over the three years. Significantly, the settlement rates of the tailings and active areas were −35 mm/a and −40 mm/a, respectively. Debris accumulation in the eastern portion of the tailings and active areas near the mountain was serious, with accumulation rates of 25 mm/a and 20 mm/a, respectively, and both had accumulation amounts of around 70 mm. For mine tailing pile areas with river flows, the pile locations and environmental restoration should be appropriately adjusted at a later stage. For gravel pile areas, regular cleaning should be carried out, especially around the mining site and at the tunnel entrances and exits, and long-term deformation monitoring of these areas should be carried out to ensure safe operation of the mining site. The SBAS-InSAR measurements were able to yield deformations with high accuracies over a wide area and cost less human and financial resources than the GNSS measurement method. Furthermore, the measurement results were more macroscopic, with great application value for surface subsidence monitoring in alpine areas.

SBAS-InSAR-Based Analysis of Surface Deformation in the Eastern Tianshan Mountains, China

“…This effort demonstrated the outstanding measurement capability of SBAS-InSAR in this region and obtained credible results. Based on this work, the parameters involved in the SBAS-InSAR processing for this paper were consistent with their settings in the literature (Mora et al, 2002;Hu et al, 2021a;Du et al, 2021b;Kursah et al, 2021), ensuring the reliability of the results, and therefore it was unnecessary to verify the accuracy of the measurement results in this study. This paper focuses on obtaining surface settlement information through SBAS-InSAR processing and analyzing settlement or uplift characteristics to understand the deformation features of the study area over a 3-year period, which will provide basic data for regional development policy formulation.…”

“…The amount of surface subsidence or uplift is also related to the frequency of natural disasters such as landslides, collapses, and debris flows. Du et al (2021b) obtained deformation information from the open-pit mining zone in the lower right corner of the study area (43.28-43.35 °N, 84.95-85.12 °E) using the SBAS-InSAR technique and compared the results with field GNSS monitoring data. This effort demonstrated the outstanding measurement capability of SBAS-InSAR in this region and obtained credible results.…”

“…Interferometric synthetic aperture radar (InSAR) technology has been developed by many researchers (Massonnet anf Feigl, 1998;Hanssen et al, 1999;Hanssen, 2001;Simons and Rosen, 2007;Lu and Dzurisin, 2014) since its introduction from microwave remote sensing (Rosen et al, 2000;Rott, 2009;Bamler and Hartl, 2010;Ye, 2010;Moreira et al, 2013;Ouchi, 2013;Monserrat et al, 2014) in the 1950s and has become a scientifically effective method of Earth observation (Massonnet and Feigl, 1998;Lu and Dzurisin, 2014), with correspondingly great achievements (Amelung et al, 1999;Mora et al, 2002;Hooper et al, 2004;Metternicht et al, 2005;Hooper, 2008;Ge et al, 2021;Kursah et al, 2021). Compared with traditional optical remote sensing, the advantage of InSAR technology lies in its ability to acquire phase information from ground objects and to be relatively less affected by weather, which in theory enables all-day, all-weather (Liu et al, 2019;Du et al, 2021a;Du et al, 2021b). Earth observation.…”

“…Moreover, it costs less time and money than manual measurements with comparable precision. Differential interferometric synthetic aperture radar (D-InSAR) (Massonnet and Feigl, 1998;Hanssen, 2001;Simons and Rosen, 2007;Lu and Dzurisin, 2014) has been developed based on InSAR technology, and multi-temporal InSAR (MT-InSAR) (Pepe and Calò, 2017;Zhu et al, 2019;Gatsios et al, 2020;Shahzad et al, 2020) including persistent scatterer InSAR (PS-InSAR) (Ferretti et al, 2001;Colesanti et al, 2003;Zhang et al, 2013;Li et al, 2020;Ge et al, 2021), small baseline subset InSAR (SBAS-InSAR) (Ferretti et al, 2001;Mora et al, 2002;Colesanti et al, 2003;Hu et al, 2021a;Du et al, 2021b), and distributed scatterer InSAR (DS-InSAR) ( Zhu et al, 2018;He and Zhao, 2020;Du et al, 2021d;Hu et al, 2021a) have been developed based on D-InSAR. Their practical scope varies, and each has its own advantages and disadvantages.…”

“…Their practical scope varies, and each has its own advantages and disadvantages. Compared with PS-InSAR, SBAS-InSAR can eliminate the influence of the atmosphere to the greatest extent (Du et al, 2021b). Currently, as more and more SAR satellites are launched, more and more SAR image data are being used for InSAR processing to monitor ground surface changes.…”