Detecting surface subsidence in coal mining area based on DInSAR technique

Coal is the primary energy resource in China. Thousands of underground coal mines are operating in China and cause severe land subsidence, leading to many environmental and engineering problems. Huainan (淮南) coal mine is the largest coal mining area in East China. Surface subsidence associated with Huainan coal mining activities has been monitoring by DInSAR (differential synthetic aperture radar) techniques in this study. Four ASAR (advanced SAR) pairs from 2009 to 2010 are selected to perform 2-pass DInSAR processing with spatial and temporal baselines suitable for subsidence monitoring. The subsidence maps generated from these pairs show that the extension of subsidence is consistent with the field observation. Quantitative measurements indicated that the magnitudes of subsidence are increased with the development of underground coal mining exploitation. This study demonstrates that DInSAR technique is effective for surface subsidence monitoring in coal mining area. Limitations and recommendations both in the adopted method and auxiliary data are also discussed.