为了消除金属棚支架在矿井瞬变电磁法探测中对电磁场分布的影响，避免对测量结果的误判。根据Maxwell方程组和有限差分原理，采用非均匀网格方法，计算并绘制不同厚度金属层影响下全空间瞬变电磁响应特征曲线，给出校正系数并对金属棚支架的影响进行校正。结果表明，无金属棚支架影响下的视电阻率值沿探测方向由15Ω��m逐渐减小至4Ω��m；而有金属棚支架影响时视电阻率值除沿探测方向逐渐减小外，深部还出现了视电阻率为3Ω��m的局部低阻异常区域；经校正后局部低阻异常区域消失，经钻孔验证为富水假异常区。通过新校正技术能有效消除矿井瞬变电磁法中金属支架的影响，避免假异常区的出现。%In order to eliminate the influence of metal support on the distribution of electromagnetic field and avoid misjudgment during roadway TEM detection,the finite difference equations with thin metal layer were deduced in this paper according to the Maxwell equations and finite difference principle.Based on the deduced equations,the whole space transient electromagnetic response curves were calculated by using non-uniform grid under conditions of different metal layer thickness,then a correction coefficient was given to correct the influ-ence of metal support.It turned out that the apparent resistivity values without the effect of metal layer varies from 15Ω·m to 4Ω·m a-long the detection direction,but under the effects of metal layer,low resistivity of about 3Ω·m exists in the deep region besides the same trend as above case.After the correction,the low resistivity region was disappear,and this result was verified by the drilling.The correction technology proposed in this paper was an effective method to eliminate the metal support influence in roadways,and avoid false anomaly generated in the mine transient electromagnetic detecting.
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