BUREAU OF ECONOMIC GEOLOGY The Universityof Texas Austin,Texas Peter T. Flawn, Director Report ofInvestigations— No. 50 Lignites of the Texas Gulf Coastal Plain By W.L.Fisher October 1963 BUREAU OF ECONOMIC GEOLOGY TheUniversity of Texas Austin, Texas Peter T.Flawn, Director Report ofInvestigations— No. 50 Lignites of the Texas Gulf Coastal Plain By W. L.Fisher October 1963 Report of Investigations No. 50 Frontispiece Operation of McKay Lignite Mining Company, Como, Texas (August 1913) Contents Page ABSTRACT 1 INTRODUCTION 2 Purpose of report 2 Acknowledgments Z Definition and geologic formation 2 Geologic and geographic distribution 5 History of mining 5 " Economic considerations. .. " ■ 7 Production in Texas 8 GENERAL FEATURES OF TEXAS LIGNITES 9 Regional variation 9 Ash content . " 9 Calorific values . 9 Fixed carbon content .. ,. 13 Volatile matter content 13 Fixed carbon/volatile matter content 13 Sulfur 13 Specific gravity 16 Thickness of seams 16 Features without significant regional variation 16 Reserves 19 Utilization 19 OCCURRENCE OF TEXAS LIGNITE 24 Wilcox lignites , 24 Anderson County . .. „ 25 Atascosa County 26 Bastrop County , 26 Bexar County 35 Bowie County 36 Caldwell County. , 37 Camp, Franklin, and Titus counties , 38 Cass County 38 Freestone County. 40 Gregg County 40 Guadalupe County 40 „ Harrison County 0 „ 42 Henderson County 47 Hopkins County 48 Lee County 50 Leon County . 51 Limestone County 53 Marion County 54 i Page Medina County 54 Milam County 57 Morris County " . 62 Nacogdoch.es County 63 Panola County 64 Rains County. 67 Robertson County . 67 Rusk County ....'. 70 Shelby County . 70 Smith County. ..■"-." 72 Uvalde County 74 Van Zandt County 75 Wood County . 76 Zavala County . 78 Miscellaneous Wilcox lignites ,. 80 Yegua lignites ............... 80 Angelina County ...» 80 Atascosa County 80 „ " Houston County ... » 81 McMullen County ....... 0 . 84 Miscellaneous Yegua lignites , 85 Jackson lignites o .......... 85 Fayette County 87 Mt. Selman lignites ............... 92 Atascosa County 92 Mt. Selman cannel coals 92 BIBLIOGRAPHY , . " . 93 APPENDIX A. ANALYSES OF TEXAS LIGNITES 104 Introduction . ,... 104 Proximate analyses 105 Ultimate analyses 115 Description of samples 118 APPENDIX B. LIGNITE MINES IN TEXAS 146 ii Illustrations Page Operation of McKay Lignite Mining Company at Como, Texas . Frontispiece Figures-- 1. Distribution of principal lignite-bearing rocks in Texas . 0 . 6 2. Lignite production in Texas. , ....... 8 3. Regional variation in ash content of Texas lignites „ . „ . 11 4. Regional variation in calorific values of Texas lignites . .. 12 5. Regional variation in fixed carbon content of Texas lignites . 14 6. Regional variation in volatile matter content of Texas lignites . " " 15 7. Regional variation in sulfur content of Texas lignites . 17 8. Regional variation in specific gravity of Texas lignites .... 18 9. Distribution of Wilcox lignites in Anderson County ...... 24 10. Distribution of lignite-bearing rocks in Atascosa County ... 25 11. Distribution of lignite deposits in Bastrop County . 26 12. Log of test boring at Glenham Station, Bastrop County .... 27 13. Diagrammatic section of bluff opposite Powell Bend, Colorado River , 29 14. Diagrammatic section of lignite in Cedar Creek, Bastrop County 30 15. Diagrammatic section of lignite in Piney Creek, Bastrop County 31 16. Diagrammatic section of lignite in Dennison Creek, Bastrop County 32 17. Diagrammatic section of lignite in Elliot Pit No. 5, Bastrop County 33 18. Diagrammatic section of lignite in pit at Dunstan Station, Bastrop County 34 19. Distribution of lignite deposits in Bexar County . 35 20. Distribution of Wilcox Group in Bowie County 36 21. Distribution of Wilcox Group in Caldwell County 37 22. Distribution of Wilcox Group in Camp, Franklin, and Titus counties 39 23. Distribution of Wilcox lignites in Cass County 39 24. Distribution of Wilcox lignites in Freestone County 41 25. Distribution of Wilcox Group in Gregg County 41 26. Distribution of Wilcox Group in Guadalupe County 42 27. Distribution of Wilcox lignites in Harrison County 43 28. Diagrammatic section, Robertson Ford, Harrison County . 43 29. Diagrammatic section, Darco mines, Harrison County .... 44 30. Distribution of Wilcox lignites in Henderson County 47 31. Distribution of Wilcox lignites in Hopkins County . 48 32. Section of lignite mined by Como Coal Company, Hopkins County 49 33. Distribution of lignite deposits in Lee County 50 iii Figures-- 34. Distribution of Wilcox lignites in Leon County 52 35. Distribution of Wilcox lignites in Limestone County 53 36. Distribution of Wilcox lignites in Marion County 54 37. Distribution of Wilcox Group in Medina County 55 38. Logs of mine shafts of Carr and Riley mines, Medina County . 56 39. Distribution of Wilcox lignites inMilam County 57 40. Log of shaft of Rockdale Mining Company, Milam County.... 58 41. Diagrammatic section, strip mine of Industrial Generating Company, Milam County 59 42. Distribution of Wilcox lignites inMorris County . 62 43. Distribution of Wilcox Group in Nacogdoches County 63 44. Distribution of lignite deposits in Panola County 64 45. Diagrammatic section of Black Shoals, Panola County 65 46. Diagrammatic section of shoals on Sabine River 66 47. Distribution of Wilcox lignites inRains County . 67 48. Distribution of lignite deposits inRobertson County 68 49. Diagrammatic section, Calvert Bluff, Robertson County .... 69 50. Distribution of Wilcox Group in Rusk County 71 51. Distribution of Wilcox Group in Shelby County 71 52. Distribution of Queen City Formation in Smith County 73 53. Distribution of lignite deposits in Uvalde County 74 54. Distribution of Wilcox Group in Van Zandt County 75 55. Distribution of lignite deposits in Wood County 77 56. Distribution of lignite deposits in Zavala County 78 57. Diagrammatic section of lignites on Nueces River, Zavala County 79 58. Distribution of Yegua Formation inAngelina County. ...... 81 59. Distribution of Yegua Formation in Houston County 82 60. Diagrammatic section, Hydes Bluff, Houston County 83 61. Section of lignite mined at Wooters Station, Houston County . 83 62. Distribution of Yegua lignite deposits in MeMullen County ... 84 63. Diagrammatic section of lignite deposits on San Miguel Creek, MeMullen County 86 64. Distribution of Manning lignites in Fayette County 87 65. Log of shaft mines south of Ledbetter, Fayette County 88 66. Diagrammatic section, Mantoon Bluff, Fayette County 89 67. Diagrammatic section of lignites on O'Quinn Creek, Fayette County 91 Tables-- 1. Average composition of Texas lignites 4 2. Stratigraphic distribution of lignite in Texas 3 3. Principal lignite deposits in Texas .. 10 4. Total estimated reserves of lignite inEocene rocks of Texas . 20 5. Estimated reserves of lignite in Texas, by county 21 iv Lignites of the Texas Gulf Coastal Plain W. L. Fisher Abstract One of the basic mineral resources of Texas is abundant deposits of lig- nite in Eocene rocks of the Gulf Coastal Plain. Currently, Texas lignites are utilized as sources of industrial fuel, activated carbon and, locally, drilling- mud additives; research indicates significant future nonfuel uses of lignite and lignitic coals. Principal deposits of lignite in the Texas Gulf Coastal Plain occur in the Wile ox Group and locally in the Yegua and Manning Formations. Southwestward along the outcrop, lignites increase in content of ash, decrease in content of volatile matter and fixed carbon, and decrease in calorific value. Highest quality lignites generally occur in the Wilcox Group in the area north of the Colorado River. Yegua and Manning lignites, and Wilcox lignites south of the Colorado River, are characterized by relatively high ash content. Existing estimates of lignite reserves in Texas are generalized owing to lack of data. Latest estimates list total recoverable, measured, and indicated reserves at approximately 4.3 billion short tons. Principal deposits of lignite occur in the following areas: (1) southern Titus County, (2) east-central Hopkins County, (3) southwestern Wood and southeastern Rains counties, (4) south-central Van Zandt County, (5) western Henderson County, (6) southern Harrison and northwestern Panola counties, (7)northwesternShelbyandnortheastern Nacogdochescounties, (8) northwestern Leon and southern Freestone counties, (9) southeastern Houston and north- central Trinity counties, (10) southwestern Houston County, (ll)Milam and northwestern Robertson counties, (12) central Bastrop County, (13) central Fayette County, (14) junction of Medina, Bexar, and Atascosa counties, (15) north-central Atascosa County, and (16) northwestern McMullen and south- central Atascosa counties. 1 2 Introduction Purpose of Report Primary purpose of this report is to outline general features of Texas lignites as an aid to possible future exploitation and utilization. In the past, Texas lignites were used primarily as fuel; at present, lignites are used in Texas as an industrial generating fuel, as a source of activated carbon, and, in the weathered or oxidized state, as a drilling-mud additive. Results of re- cent research indicate that future nonfuel as well as specialized fuel uses of lignite should be significant. Acknowledgments The writer expresses appreciation to P. T. Flawn, Director, Bureau of Economic Geology, The University of Texas, for support and interest in the course of this study and for reading critically the manuscript; and to D. W. Kohls and P.U. Rodda, Bureau of Economic Geology, for reading the manu- script