Underground Coal Fires Identification and Monitoring Using Time-Series InSAR With Persistent and Distributed Scatterers: A Case Study of Miquan Coal Fire Zone in Xinjiang, China

Abstract

The Xinjiang is an important coal production base in China and also a serious coal fire disaster area. Coal fires not only waste resources, but also cause air pollution and damage to the ecological environment. Hence, it is very important to identify and monitor the underground coal fire areas accurately and efficiently for the control of coal fires. Interferometric synthetic aperture radar (InSAR) technology identifies and monitors coal fire areas by monitoring surface subsidence caused by burned out area. Compared with traditional coal fire monitoring technology, InSAR technology has the advantages of allweather and high efficiency. But the fire areas are often distributed in wild areas, this factor significantly limits the application of the traditional Persistent Scatterer interferometry (PSI) technology. In addition, Xinjiang coal fires are mostly located in historical goafs, so it is necessary to distinguish the subsidence caused by mining and coal fires. Therefore, distributed scatterer interferometry (DSI) technology is used to monitor the Miquan fire area in Xinjiang in this paper. The results show that compared with PSI technology, DSI technology can expand the number of effective monitoring points 124 times. On this basis, spatiotemporal analysis of surface subsidence in the study area suggests that the subsidence caused by mining and coal fires exhibits significantly different space-time evolution rules. Therefore, in the future, the coal fire area and mining area can be separated and identified according to these rules. The final identified coal fire area contains all measured coal fire points, and accurately monitors the fire extinguishing area. INDEX TERMS Coal fire monitoring, subsidence information, InSAR, spatio-temporal analysis.

Impact of SAR Image Resolution on Polarimetric Persistent Scatterer Interferometry With Amplitude Dispersion Optimization

“…D UE to its high efficiency and millimeter accuracy of deformation monitoring, persistent scatterer interferometry (PSI) [1]- [8] with synthetic aperture radar (SAR) data has been routinely used in terrain and infrastructures displacement detection and monitoring. Despite its successful performance in monitoring ground deformations related to subsidence [9], landslides [10], earthquakes, and other geological environmental hazards [11], [12], in some areas, conventional PSI techniques may suffer from the lack of acceptable densities of coherent scatterers. In the areas, such as the vegetated ones, pixels may be affected by severe decorrelation [13], thus making their phases noisy and unqualified for PSI applications.…”

Monitoring Subsidence Deformation of Suzhou Subway Using InSAR Timeseries Analysis

“…In the past, such measurements mainly rely on conventional geodetic tools such as leveling, GNSS, etc., which has the disadvantages of high time and economic cost. Synthetic aperture radar interferometry (InSAR) shows its unique advantages of large spatio-temporal coverage [11], [12]. It also overcomes the limitations of traditional geodetic methods, and makes it possible to derive the largescale subsidence deformation fields quickly and in large area.…”

Mining Subsidence Monitoring With Modified Time-Series SAR Interferometry Method Based on the Multi-Level Processing Strategy

“…Advanced time-series interferometric synthetic aperture radar (ATS-InSAR) method refers to those TS-InSAR methods that combine the PS and distributed scatterer (DS) monitoring modules [21], [22]. As we all know, the SqueeSAR algorithm [23] was put forward to select MP correspond to image pixels belonging to the available dataset of no less than moderate coherence.…”