UNITED STATES MINERAL RESOURCES 



OIL SHALE 



By William C. Culbertson and Janet K. Pitman 



CONTENTS 



Abstract of conclusions 497 



Introduction 497 



Oil-shale deposits in the United States 498 



Lacustrine oil-shale deposits 498 



Marine black shale deposits 499 



Shale associated with coal beds 499 



Resources 500 



Identified and hypothetical resources of shale oil 500 



Green River Formation 500 



Chattanooga Shale and equivalent forma- 

 tions 500 



Other shale deposits 501 



Foreign oil-shale deposits 501 



Speculative resources 501 



Prospecting techniques 502 



Problems for research 502 



Selected references 503 



TABLES 



95. 



96. 



Shale-oil resources of the United States, in bil- 

 lions of barrels, by grade (oil yield) of oil 

 shale 



Shale-oil resources of the world (excluding the 

 United States) in billions of barrels, by grade 

 (oil yield) of oil shale 



500 



501 



ABSTRACT OF CONCLUSIONS 



Oil shale, a fine-grained sedimentary rock containing in- 

 ■Eoluble organic matter that yields substantial amounts of 

 oil by destructive distillation, occurs in large volumes 

 throughout the United States and the world, and constitutes 

 an enormous resources of oil. Identified resources of shale 

 oil in the United States total about 2 trillion barrels of oil 

 in shale that yields an average of 15 or more gallons of oil 

 per ton, most of which is in the lacustrine rocks of the 

 Eocene Green River Formation of Colorado, Utah, and Wyo- 

 ming. Although no oil is being produced from oil shale in 

 the United States, it seems likely that oil from high-yield 

 shales will be needed in the near future to supplement other 

 sources of energy. It is estimated that 0.42 trillion barrels 



of oil are in oil shale that yields 30 or more gallons of oil 

 per ton, 85 percent of which is in western Colorado. Min- 

 erals locally associated with the rich oil shale may yield 

 recoverable sodium carbonate, sodium bicarbonate, or 

 aluminum. 



Marine black shales occur in many parts of the United 

 States and form an immense, but low-grade resource of 

 shale oil. The better parts of these deposits generally yield 

 only 10-15 gallons of oil per ton, but hydrogenation or simi- 

 lar techniques may increase the yield by 50 to 100 percent. 

 Another widespread resource of shale oil may be the car- 

 bonaceous shales associated with coal beds. The total re- 

 sources of shale oil to depths of 20,000 feet may total 26 

 trillion barrels in low-yield shales and 1.3 trillion barrels 

 in high-yield shales. 



INTRODUCTION 



Oil shale is a fine-grained sedimentary rock con- 

 taining organic matter that has the property of yield- 

 ing substantial amounts of oil when heated in a 

 closed retort (destructive distillation) but that is 

 mostly insoluble in ordinary petroleum solvents. The 

 United States has tremendous quantities of oil shade, 

 principally in the Green River Formation in Colo- 

 rado, Utah, and Wyoming. These three States con- 

 tain identified resources of about 1.8 trillion barrels 

 of oil in oil shale that yields an average of 15 or more 

 gallons per ton. However, no oil-shale venture has 

 been a commercial success in the United States in the 

 last 100 years, despite the fact that other countries 

 of the world have for many years burned oil shale as 

 a fuel, or have produced oil or combustible gas from 

 the shale. The principal reason for the lack of suc- 

 cess is the abundant supplies of lower cost oil, gas, 

 and coal that this country has developed. The rising 

 demand for energy, however, may soon require the 

 development of this abundant energy resource to 

 supplement the dwindling supplies of other fossil 

 fuels. 



Duncan and Swanson (1965, p. 5) have estimated 

 that about 400 million barrels of oil have been pro- 

 duced from oil shale in foreign countries prior to 



U.S. GEOL. SURVEY PROF. PAPER 820 



497 



