Coal Resources of the - United States, " January 1,1 * GEOLOGICAL SURVEY BULLETIN 1412 > Coal Resources of the ' - % United States,y January 1,1974 By PAUL AVERITT GEOLOGICAL SURVEY BULLETIN 1412 <- /4 summary of information concerning the quantity and distribution of coal in the United States. Supersedes Bulletin 1275 UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1975 UNITED STATES DEPARTMENT OF THE INTERIOR GEOLOGICAL SURVEY V. E. McKelvey, Director Library of Congress Cataloging in Publication Data Averitt, Paul, 1908- Coal resources of the United States, January 1, 1974. (Geological Survey Bulletin 1412) "Supersedes Bulletin 1275." Bibliography: p. Includes index. Supt.ofDocs.no.: 119.3:1412 1. Coal-United States. I. Title. II. Series: United States Geological Survey Bulletin 1412. QE75.B9 No. 1412 [TN805.A5] 557.3'08s [553'.2'0973] 75-619188 For sale by the Superintendent of Documents, U. S. Government Printing Office Washington, D. C. 20402 Stock Number 024-001-02703-8 CONTENTS Page Abstract........................................................................................................................... 1 Introduction.................................................................................................................... 2 Conversion to metric system ................................................................................... 4 Acknowledgments........................................................................................................... 4 Distribution of coal in the United States....................................................................... 4 Number of coal beds................................................................................................ 7 Main structural basins............................................................................................. 8 Coal resources................................................................................................................. 9 Identified resources.................................................................................................. 10 Methods of preparing and reporting estimates ............................................... 10 Classification according to characteristics of the coal............................. 16 Rank of coal....................................................................................... 16 Grade of coal...................................................................................... 21 Specific gravity of coal....................................................................... 21 Thickness of beds............................................................................... 23 Areal extent of beds............................................................................ 25 Thickness of overburden.................................................................... 25 Classification according to reliability of estimates .................................. 26 Measured resources........*.................................................................... 26 Indicated resources............................................................................. 26 Demonstrated resources...................................................................... 27 Inferred resources............................................................................... 27 Unclassified resources........................................................................ 27 Distinction between original, remaining, and recoverable resources...... 27 Original resources.............................................................................. 27 Remaining resources.......................................................................... 28 Recoverable resources......................................................................... 28 Percentage of coal recovered in past mining............................................ 29 Underground mining......................................................................... 29 Strip mining....................................................................................... 31 Auger mining..................................................................................... 31 Depletion of resources............................................................................... 31 Computer methods of estimating resources ............................................. 31 Statistical methods of estimating resources.............................................. 32 Reserve base...................................................................................................... 32 Distribution of identified resources in selected categories .............................. 33 Distribution according to: Region....................................................................................................... 34 Rank.......................................................................................................... 36 Thickness of overburden........................................................................... 38 Reliability of estimates.............................................................................. 38 Thickness of beds...................................................................................... 39 Combined categories of overburden, reliability, and thickness of beds... 39 Estimates for States not covered by cited reports............................................. 41 Maryland................................................................................................... 41 Other States...............................................................................'................ 42 in IV CONTENTS Coal resources Continued Page- Hypothetical resources............................................................................................ 43 Speculative resources............................................................................................... 45 Coal more than 6,000 feet below the surface................................................... 46 Coal on the continental shelves....................................................................... 46 Need for additional work ............................................................................................... 47 Previous estimates of United States coal resources........................................................ 47 M. R. Campbell, 1909-29........................................................................................ 48 Comparison between the Campbell estimate and the present estimate.......... 49 Difference in estimates in the 0- to 3,000-foot overburden category........ 49 Difference in estimates in the 3,000- to 6,000-foot overburden category. 50 Summation and appraisal of the Campbell estimate............................... 50 United States Coal Commission Committee report, 1922...................................... 51 United States Army Corps of Engineers, 1952........................................................ 52 Coking-coal resources..................................................................................................... 52 Low-volatile bituminous coal................................................................................. 53 Strippable coal resources ................................................................................................ 54 Reclamation of strip-mined lands........................................................................... 56 Peat resources.................................................................................................................. 58 Nonbanded coals............................................................................................................. 59 Cannel coal.............................................................................................................. 59 Boghead coal............................................................................................................ 59 Intermediate varieties............................................................................................... 60 Uses.......................................................................................................................... 60 Production of coal in the United States......................................................................... 60 Concentration of resources and production in selected beds................................. 63 Mammoth coal zone......................................................................................... 63 Pittsburgh bed.................................................................................................. 64 Lower Kittanning (No. 5 block) bed ............................................................... 64 Upper Freeport bed.......................................................................................... 65 Campbell Creek (No. 2 gas) bed ..................................................................... 65 Upper Elkhorn No. 3 bed................................................................................ 66 Fire Clay bed .................................................................................................... 66 Pocahontas beds............................................................................................... 66 Sewell bed......................................................................................................... 67 Sewanee bed.....................................................................................................