Land subsidence monitoring and spatiotemporal evolution characteristics analysis of Datong coalfield，Shanxi Province based on time series InSAR

TONG Yunxiao; YANG Junquan; WANG Xue; TAN Kun

doi:10.12029/gc20221215001

GEOLOGY IN CHINA > 2024 > 51(1): 170-183. > DOI: 10.12029/gc20221215001

Tong Yunxiao, Yang Junquan, Wang Xue, Tan Kun. 2024. Land subsidence monitoring and spatiotemporal evolution characteristics analysis of Datong coalfield，Shanxi Province based on time series InSAR[J]. Geology in China, 51(1): 170−183. DOI: 10.12029/gc20221215001

Citation:

Land subsidence monitoring and spatiotemporal evolution characteristics analysis of Datong coalfield，Shanxi Province based on time series InSAR

TONG Yunxiao^{1, 2,},
YANG Junquan^{1, 2, ,},
WANG Xue^{3, 4},
TAN Kun^{3, 4}

1.
Tianjin Centre, China Geological Survey, Tianjin 300170, China
2.
North China Center for Geoscience Innovation, Tianjin 300170, China
3.
School of Geographic Science, East China Normal University, Shanghai 200241, China
4.
Key Laboratory of Geographic Information Science (Ministry of Education), East China Normal University, Shanghai 200241, China

Funds: Supported by the project of China Geological Survey “Dynamic Monitoring and Risk Assessment of Natural Resources in North China” (No. DD20211388).

More Information

Author Bio:
TONG Yunxiao, male, born in 1994, master, engineer, mainly engaged in the research of InSAR deformation monitoring and natural resources survey monitoring; E-mail: tyunxiao@126.com
Corresponding author:
YANG Junquan, male, born in 1980, doctor, senior engineer, mainly engaged in the research of petrology and natural resources survey monitoring; E-mail: dap-yangjunquan@163.com.
Received Date: December 14, 2022
Revised Date: February 27, 2023
Available Online: February 03, 2024

Graphical Abstract

Abstract

Abstract

This paper is the result of environmental geological survey engineering.
Objective
Land subsidence is one of the main geological hazards in coal mine area, which seriously affects the sustainable development of mining economy and the safety and stability of residents' life. It is necessary to conduct rapid and efficient monitoring of land subsidence in the mining area.
Methods
Taking Datong coalfield as an example, the 31 scenes Sentinel-1 images acquired from January 2020 to December 2021 were used to monitor the land subsidence based on Small Baseline Subset InSAR (SBAS−InSAR) technology. The land subsidence rate and cumulative subsidence results of Datong coalfield were obtained. Moreover, the reliability of the monitoring results was verified using existing research results, and the spatiotemporal variation characteristics and evolution laws of subsidence were analyzed.
Results
The results indicate that the land subsidence in the Datong coalfield is extensively distributed, and its overall distribution of subsidence is basically consistent with the trend of mining management data. The subsidence is mainly distributed in the west of Nanjiao County of Datong City and the junction of Datong City, Huairen City and Shanyin County, among which the land subsidence of Tashan mine is the most severe. The subsidence characteristics of Datong coalfield mainly include the maximum subsidence rate of 168.03 mm/a, the maximum cumulative subsidence amount of 329.12 mm, and the total subsidence area of 270.95 km². Overall, there is a continuous increase in subsidence, and it takes a significant amount of time to achieve relative stability in surface activities in accordance with this trend.
Conclusions
This study shows the feasibility of InSAR technology in subsidence monitoring in coal mine area, which can provide a new technical for mineral resources management work, and the research results can provide scientific basis for subsidence monitoring and warning, disaster prevention and control, and rational development and utilization of resources in coal mine area.
Highlights
This paper utilizes SBAS−InSAR technology to conduct a long−term monitoring of land subsidence in Datong mining areas, highlights the spatiotemporal variation characteristics and evolution laws of subsidence in coal mine areas, and confirms the feasibility of InSAR technology in mineral resources management work, hoping to promote the subsidence monitoring research and reasonable management of natural resources.

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References (67)

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Land subsidence monitoring and spatiotemporal evolution characteristics analysis of Datong coalfield，Shanxi Province based on time series InSAR

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