Abstract:With high resolution for shallow exploration, Ground Penetrating Radar (GPR) provides an significant means for exploring typical geological structures like loose coal seam and goaf in the coalfield combustion area. However, it is difficult for GPR to distinguish various kinds of burning geological structures and delineate the key combustion area because of shortage of theories. Based on electromagnetic wave theory, the authors conducted forward simulation of the geoelectric models of typical burned coal in the coalfield combustion area by using Finite Difference Time Domain (FDTD). The radar response characteristics of numerical computation indicate that serious diffracted waves appear from the part of loose collapse coal seam, and reflected waves from the top of the cavity have high energy and are continuous. Forward simulation and field test demonstrate that, with GPR, we can distinguish the loose degree of the burning coal seam and delineate the key combustion area so as to reduce the cost of fire-fighting. This is of great significance for safe combustion mining.
胡明顺, 潘冬明, 董守华, 李娟娟. 煤火区浅部松散煤体及采空区的探地雷达响应特征[J]. 物探与化探, 2012, 36(4): 598-601,606.
HU Ming-shun, PAN Dong-ming, DONG Shou-hua, LI Juan-juan. GPR RESPONSE CHARACTERISTICS OF SHALLOW LOOSE COAL SEAM AND GOAF IN THE COALFIELD COMBUSTION AREA. Geophysical and Geochemical Exploration, 2012, 36(4): 598-601,606.
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