It is urgently needed to identify lower boundary of a burning coal seam and water yield property nearby in a Tianshan coal exploration area, Xinjiang. Based on comprehensive analyses of geological data and physical property parameters, then geophysical prospecting methods mainly magnetic method and TEM were used. The magnetic prospecting grid is designed as 20m×80m, and prospecting lines in the west have been lengthened in later stage. According to prospecting area measured magnetic anomaly distribution map, magnetic anomaly distribution map after low-pass filtering, continuation upward 30m magnetic anomaly distribution map and vertical second-order derivative magnetic anomaly distribution map delineated burning areas are mainly distributed in the north part of the prospecting area. Designed TEM prospecting grid 40mx80m, based on floor water yield anomaly distribution maps of L1, L5 and L10 coal seams have interpreted better water yield areas of L1 and L5 floors are mainly concentrated in north part, highly in accordance with burning area bounds; while water yield property of L10 floor is very uneven, only near coal seam outcropped north area because of impact from sandstone fissures, taking in from precipitation and formed scattering sandstone fissure better water yield areas. The interpreted results after coalmine side verification are considered basically reliable.%新疆天山某煤炭勘查区,需查明一水平内火烧煤层的下边界及其富水性.在综合分析该区地质资料及物性参数的基础上,采用了以磁法和瞬变电磁法为主的物探方法.磁法勘探测网设计为20m×80m,并在后期对西部测线进行了加长.根据测区实测磁异常分布图、低通滤波后磁异常分布图、向上延拓30m磁异常分布图及垂向二阶导数磁异常分布图,圈定火烧区主要分布在测区的北部.瞬变电磁法勘探测网设计为40m×80m,依据下1、下5及下10煤层底板富水异常分布图,解释下1、下5煤底板的富水性主要集中在测区的北部,与火烧区范围高度一致,而下10煤层底板富水性极不均匀,仅在测区北部煤层露头附近,受砂岩裂隙的影响,接受降水补给形成零星砂岩裂隙富水区.该解释成果经矿方钻孔验证,结论基本可靠.
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