The XVIII International Conference on Mine Surveying

129 / 2023-06-30 09:02:27

内蒙古新井露天矿边坡坍塌多源遥感精细监测及分析

Multi-source remote sensing; D-InSAR; DS-InSAR; Surface deformation; Open pit mine

Open-pit mining has the advantages of a short construction period, large mining scale, low production cost, and high resource recovery rate. At present, the depth of open-pit mining is increasing, the slope height and disturbance area are further increased, moreover，the stability of the slopes of opencast mines is affected by a variety of factors such as local geological formations, ithology, precipitation and mining activities,so the problem of slope instability is becoming more and more serious. Therefore, it is important to monitor the slope and evaluate its stability for the production safety of open-pit mines. Conventional ground monitoring technologies such as GNSS（Global Navigation Satellite System）, leveling, total station are difficult to fully obtain the temporal and spatial variation information of the whole mining area. Fortunately, remote sensing can overcome these limitations because of its wide-coverage advantages, short revisit period, high economic benefits, and rich access to information. In this paper, taking Xinjing Open-pit Mine, Inner Mongolia as the study area, the remote sensing interpretation, D-InSAR, and DS-InSAR methods were employed to monitor the collapse area and dump slope on 22 February 2023 based on GF-2, Radarsat-2, and Sentinel-1A data. The results show that: (1) The deformation of the discharge fields' slopes happened during the observation period, and the combination of topography and time-series deformation results inferred a low risk of landslides in these areas. (2) The monitor results obtained from Radarsat-2 show that the deformation in the landslide collapse area is large, with a maximum deformation value of -70 mm in 23 days. (3) During the monitoring period of Setinel-1A and Radarsat-2 near the back wall boundary of the collapse area, the deformation trend transitioned from large to small to small to large, which may be due to the initial deformation stage during the Sentinel-1A monitoring period, and after the Radarsat-2 monitoring time, The collapse surface gradually formed and began to slide down as a whole, and the center of gravity of the collapse gradually decreased.(4)The landslide collapse may be due to the combined effects of local geotechnical properties, temperatures, groundwater, and coal fires and early underground mining activities. Specifically, the stress concentration phenomenon or stress blocking occurs at the bottom of the slope, and the slope collapse will happen along the slip surface when the stress exceeds the maximum threshold value. (5) The multi-source remote sensing technology can comprehensively and accurately monitor the spatial-temporal changes, and then effectively identify and locate potential risk high-risk areas, which is of great significance for pre-disaster warning and post-disaster relief.