The Coal Measures Strata are divided into 1 super-sequence and 3 sequences on the basis of paleostructure surface,widespread overlap unconformability,coal seam,and channel lag deposit. 根据古构造运动面、大面积超覆界面、煤层和河床滞留沉积将含煤岩系划分为1个超层序和3个层序。
Then, to reach the buried coal seams, explosives are used to remove up to 800 feet of mountain elevation.
然后, 为了到达埋藏的煤层,使用炸药移除高达 800 英尺的山体高度。
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You will then walk along the low passages cut in the coal seam, and you will see men with pick-axes breaking down and cutting out great blocks of the coal.