The application of SOTEM method to populated areas: A case study of Fangzi coal mine goaf
CHEN Da-Lei1,2(), CHEN Wei-Ying3, GUO Peng1,2, WANG Run-Sheng1,2, WANG Hong-Jun1,2, ZHANG Chao1,2, MA Qi-He4, HE Chun-Yan1,2
1.Shandong Geophysical and Geochemical Exploration Institute, Jinan 250013, China 2.Shandong Geological Exploration Engineering Technology Research Center,Jinan 250013,China 3.Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China 4.Shandong Zhengyuan Geological Exploration Institute, China Metallurgical Geology Bureau, Weifang 261057, China
Transient electromagnetic method (TEM) is the main tool for detecting mined-out area. However, when the goaf is buried deep or there are many buildings in the survey area, it is often difficult for the traditional loop source device to meet the detection needs. SOTEM has such advantages as high signal amplitude, strong signal-to-noise ratio, large detection depth, and convenient and efficient construction. The buried depth of the goaf in the Fangzi coal mine in Weifang City is about 500 meters, and most of the area is in villages where houses are densely distributed. In order to effectively detect the distribution and influence range of the goaf under Jiangjia Village, the authors adopted SOTEM method to carry out the detection work. The problem of building obstacle was overcome by placing transmitting source outside the village and using portable receiving device to receive signal in the village. Wavelet denoising and five-point smoothing technology were used to filter the strong interference data, and then OCCAM method was used to carry out one-dimensional inversion of the data. The results show that the depth of SOTEM detection reached 800 meters, and the distribution range of low-resistance goaf was successfully delineated, which was later verified by drilling.
陈大磊, 陈卫营, 郭朋, 王润生, 王洪军, 张超, 马启合, 贺春燕. SOTEM法在城镇强干扰环境下的应用——以坊子煤矿采空区为例[J]. 物探与化探, 2020, 44(5): 1226-1232.
CHEN Da-Lei, CHEN Wei-Ying, GUO Peng, WANG Run-Sheng, WANG Hong-Jun, ZHANG Chao, MA Qi-He, HE Chun-Yan. The application of SOTEM method to populated areas: A case study of Fangzi coal mine goaf. Geophysical and Geochemical Exploration, 2020, 44(5): 1226-1232.
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