Abstract:It is usually considered that TEM detection which uses the signal of secondary induction field is influenced little by the topography. Based on many years' production practice, however, the authors have found that the influence of topography should not be neglected. Due to the relatively shallow burial of the coal seam, TEM detection in the coal field is influenced considerably by the topography. Using the commonly used depth calculation formula in the coal field, the authors calculated the influence extent of topographic variation on induced electromotive force and on attenuation time separately. Then, the two influencing factors substituted for parameters so as to recalculate the apparent resistivity. According to the new apparent resistivity calculation depth, a set of practical topographic correction methods for the coal measure strata could be obtained. Lastly, by designing the corresponding software, the comparative profiles before and after correction can be displayed in real-time. The theoretical model and actual data have proved the effectiveness of this method and the software.
范涛. 煤田电法勘探中的TEM地形校正方法[J]. 物探与化探, 2012, 36(2): 246-249.
FAN Tao. TEM TOPOGRAPHIC CORRECTION IN COAL FIELD ELECTRICAL EXPLORATION. Geophysical and Geochemical Exploration, 2012, 36(2): 246-249.