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 10 - Determination of areas of reliability from points of measurement along outcrop line, supplemented by mine and drill-hole data |
Created by the EERT WWW Staff.
[an error occurred while processing this directive]
