煤田勘查钻孔见煤前的一般岩性特征

General Lithologic Features Before Drilling to The Coal－beds in Drill－hole of Coal－field Exploration

根据多年的勘查实践，总结提出了八条正常地层层序下钻孔见煤前的一般岩心岩性特征，对指导见煤预告等大有裨益。

Based on the prospecting practices of many years, the paper has summarized 8 general lithologic features of core under normal stratigraphic sequence before drilling to the coal－beds in drill hole. It is helpful to predict the depth of coal－beds in drill hole.