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在定向钻探中，利用分枝孔勘探陡倾斜矿体、地表有较大障碍物的深部矿体、或者上部有较厚覆盖层或严重漏失坍塌层的深部矿体，是一
In directional drilling, the use of branch holes for the exploration of steeply sloping ore bodies, deep ore bodies with large obstacles on the surface or deep ore bodies with thick overburden or serious loss of collapsed layers in the upper part are