Coal Resource Classification System of the U.S. Geological Survey
By Gordon H. Wood, Jr., Thomas M. Kehn, M. Devereux Carter, and William C. Culbertson
GEOLOGICAL SURVEY CIRCULAR 891
Figure 19 - Areas of reliability, overburden contours, and coal thickness isopachs to accompany figure 18 |
Created by the EERT WWW Staff.
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