Petroleum Potential of Wilderness Lands in , Wyoming-Utah-Idaho Thrust Belt by Richard B
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Petroleum Potential of Wilderness Lands in , Wyoming-Utah-Idaho Thrust Belt By Richard B. Powers P~TROLEUM POTENTIAL OF WILDERNESS LANDS IN THE WESTERN UNITED STATES GEOLOGICAL SURVEY CIRCULAR 902-N j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j j CONTENTS Page Abstract---------------------------------------------------------------------- N1 Acknowledgments-------------------------------------------------------------- 1 Introduction------------------------------------------------------------------- 1 Geologic framework ------------------------------------------------------------ 1 Petroleum potential factors ------------------------------------------------------ 4 Reservoirrocks------------------------------------------------------------- 4 Sourceandsealrocks -------------------------------------------------------- 4 Structure------------------------------------------------------------------ 7 Oilandgasfields--------------------------------------------------------------- 7 Productive trends---------------------------------------------------------- 9 Qualitative ratings of Wilderness Lands-------------------------------------------- 9 ~ethodsofevaluation-------------------------------------------------------- 9 Petroleum potential ratings--------------------------------------------------- 11 Summary--------------------------------------------------------------------- 13 Referencescited----------~----------------------------------------------------- 13 ILLUSTRATIONS Page FIGURE 1. ~ap showing location and boundaries of the Wyoming-Utah-Idaho Thrust Belt province------------------- N2 2. Index map of Wyoming-Utah-Idaho thrust belt showing principal tectonic features, major thrust faults, oil and gas fields, and new-field wildcat discovery wells sit:lce 1975----------------------------------------- 3 3. Diagrammatic west to east structural cross section in vicinity of Summit County, Utah, and Yellow Creek field, Uinta County, Wyoming, showing the relation between an anticline in the "hanging wall" and rocks in the "footwall" (subthrust block)------------------------------------------------------- 5 4. Generalized stratigraphic chart of the Wyoming-Utah-Idaho thrust belt showing productive formations and known or potential reservoir and source rocks. (~odified from Hayes, 1976; Powers, 1977; 1983; Lageson and others, 1980; and Ver Ploeg and De Bruin, 1982) ------------------------------------------------- 6 5. Structure contour map of the Whitney Canyon-Carter Creek field, Wyoming----------------------------- 10 6. Simplified west-east structural cross section across Whitney Canyon-Carter Creek field in the Wyoming-Utah Idaho thrust belt showing hanging wall fold closed against the Tunp thrust ----.:...--..,...------------------- 11 TABLE Page TABLE 1. New fields discovered since 1975 and indicated recent new-field wildcat discoveries in the Wyoming-Utah-Idaho thrustbelt--------------------------------------------------------------------------------- N8 III PETROLEUM POTENTIAL OF WILDERNESS LANDS IN THE WESTERN UNITED STATES Petroleum Potential of Wilderness Lands in Wyoming-Utah-Idaho Thrust Belt By Richard B. Powers ABSTRACT INTRODUCTION Three segments of the North American part of the Cordil leran thrust belt (north of Mexico) produce oil and gas-the A review has been made of the oil and gas po Canadian Foothills, western Montana, and Wyoming-Utah Idaho thrust belts. Between 1975 and 1983, 26 new (or indi tential of various categories of Wilderness Lands cated new) fields (at least 8 of them "giants") were found in the in the Wyoming-Utah-IdahoThrust Belt province Wyoming-Utah-Idaho thrust belt; these fields have an esti (fig. 1). The types of Wilderness Lands are shown mated, ultimately recoverable 3.2 billion barrels of oil (BBO) on maps of Wyoming, Utah and Idaho prepared and 16.5 trillion cubic feet (TCF) of gas, plus natural gas liq by the U.S. Bureau of Land Management uids. Most of this oil and gas is trapped in major (>50 MMBO, or >0.3 TCF of gas) and giant (100 MMBO, or 1 TCF of gas) (1981a,b,c). Tract numbers evaluated in the pre fields, and not in numerous, smaller-size fields. This is signifi sent study are shown on these maps. Six of the cant because over 80 percent of the world's discovered oil and wilderness tracts have a high oil and gas potential, gas is in giant fields, and giant fields account for as much as one has a medium potential, and the remainder 70 percent of the world's present production. have either zero, low, or unknown oil and gas po Four major thrust plates, which are oriented, generally, from north to south, are. recognized in the province. All 26 tential. fields discovered since 1975 are concentrated mainly in the The Wyoming-Utah-Idaho thrust belt straddles southern one-third of the thrust belt and are located on, and parts of western Wyoming, north-central Utah, controlled by, the folded leading edges of three of the four and eastern Idaho and covers an area of 15,000 major thrust plates. Six wilderness tracts within the province square miles (fig. 1). The northern boundary is are rated as having a high potential for the occurrence of oil and gas, one has a medium potential, and the remainder have placed at the south edge of the Snake River vol either zero, low, or unknown oil and gas potential. canic plain west of Jackson, Wyoming; the south ern boundary is at the intersection of the Uinta ACKNOWLEDGMENTS Mountains just east of Salt Lake City; the eastern boundary is at the surface trace of the Darby The many, detailed reports on the surface geol Prospect thrust fault, which separates the struc ogy and mineral potential of wilderness areas pub turally deformed thrust belt from the undeformed lished by colleagues in the U.S. Geological Survey Green River basin on the east; the western bound were a valuable source of information. I would like ary is the surface trace of the Willard-Paris thrust particularly to thank Steven S. Oriel for his help on the east side of the Bear River Range (fig. 2). ful discussions on the overall surface geology of the thrust belt. Jerome W. Boettcher of Exxon GEOLOGIC FRAMEWORK Co. USA provided me with up-to-date information on the status of new-field wildcat gas discoveries During a span of geologic time (Paleozoic-early in the area west of La Barge, Wyoming, that Mesozoic) ranging from about 570 to 140 million aided greatly in the evaluation of tracts in that years (m.y.) before the present, more than 60,000 area. feet of sand, silt, mud, and limy material was de- N1 SOUTHWESTERN I I WYOMING EASTERN BASIN II II BASINS AND RANGE 0 100 200 MILES FIGURE 1.-Map showing location and boundaries of the Wyoming-Utah-Idaho Thrust Belt province in respect to the other petroleum provinces in the northern Rocky Mountain region. N2 BASIN Pinedale• BIG PINEY-LaBARGE PRODUCING COMPLEX GREEN RIVER BASIN EXPLANATION Quaternary and Tertiary volcanic rocks Precambrian rocks, u ndi ffe rentiated ..._...., Thrust fault (sawteeth on overthrust block) , Producing oil and gas fields and indicated new discoveries 0 10 20 30 MILES FIGURE 2.-Index map of Wyoming-Utah-Idaho thrust belt showing principal tectonic features, major thrust faults, oil and gas fields (numbered), and new-field wildcat discovery wells since 1975. Numbers coded to field names are shown on table 1. Cross section A-A ' shown in fig. 3 (Modified from Powers, 1977, 1980; Lamerson and Royse 1980; Petroleum Information, 1981; and Ver Ploeg and De Bruin, 1982). Cross section B-B' is shown in figure 5. N3 posited in an ocean basin that was located some tive to the forming of a trap. All of these factors distance west of the present thrust belt. About are present in the Wyoming-Utah-Idaho thrust 140 m.y. ago, in latest Jurassic time, the ocean belt. basin (or miogeosyncline) began to be deformed, and the mass of sedimentary rocks within it was RESERVOIR ROCKS strongly folded and thrust eastward by compres Fifteen formations produce oil or gas in anticli sional forces from the west. Compression con nal traps in the thrust belt~ These formations rep tinued episodically for about 85 m.y., or until resent eight different geologic systems, ranging in early Eocene time (55 m.y.) after which normal age from Cretaceous through Ordovician (fig. 4). (extensional) faulting occurred within the thrust In contrast, many producing basins in the United fold belt until the present. Eastward horizontal States have only one or two formations within a movement on most of the individual thrust sheets single geologic period that are oil or gas bearing. exceeds 5 miles. Rocks of the Jurassic and Triassic Systems con Four major thrust-fault systems are recognized tain six reservoir formations that are productive in this province and are named after the major of oil or gas, including the prolific Nugget thrusts involved (fig. 2). They are from oldest to Sandstone,. which is the main oil or gas reservoir youngest, and from west to east: (1) Willard in 11 fields. Paleozoic rocks contain five productive Paris, (2) Meade-Crawford, (3) Absaroka, and (4) reservoirs ranging in age from the Permian Phos Darby-Prospect-Hogsback (Royse, 1979). Prior to phoria Formation through the Ordovician Bighorn horizontal shortening of some 65 miles due to Dolomite. These formations are the major gas and west-east folding and thrusting, the width of this condensate (light, high gravity crude oil similar to rock sequence was about 130 miles. The chief natural gasoline) reservoirs in seven recently