Chapter 3 Geologic Assessment of Undiscovered Oil and Gas Resources in the Phosphoria Total Petroleum System of the Wind River Basin Province, Wyoming Volume Title Page By M.A. Kirschbaum, P.G. Lillis, and L.N.R. Roberts

Chapter 3 of Petroleum Systems and Geologic Assessment of Oil and Gas in the Wind River Basin Province, Wyoming

Compiled by USGS Wind River Basin Province Assessment Team

U.S. Geological Survey Digital Data Series DDS–69–J

U.S. Department of the Interior U.S. Geological Survey U.S. Department of the Interior DIRK KEMPTHORNE, Secretary U.S. Geological Survey Mark D. Myers, Director

U.S. Geological Survey, Reston, Virginia: 2007

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Suggested citation: Kirschbaum, M.A., Lillis, P.G., and Roberts, L.N.R., 2007, Geologic assessment of undiscovered oil and gas resources in the Phos- phoria Total Petroleum System of the Wind River Basin Province, Wyoming, in USGS Wind River Basin Province assessment team, Petroleum systems and geologic assessment of oil and gas in the Wind River Basin Province, Wyoming: U.S. Geological Survey Digital Data Series DDS–69–J, ch. 3, 27 p.

ISBN 1-4113-2027-7 iii

Contents

Abstract… ……………………………………………………………………………………… 1 Introduction……………………………………………………………………………………… 1 Structural Geology… …………………………………………………………………………… 3 Phosphoria Total Petroleum System… ………………………………………………………… 5 Source Rocks… …………………………………………………………………………… 6 Oil Characterization and Distribution… …………………………………………………… 6 Maturation and Migration…………………………………………………………………… 7 Stratigraphic units and reservoir rocks……………………………………………………… 8 Madison Limestone (Mississippian)… ………………………………………………… 8 Amsden Formation (Mississippian and Pennsylvanian)… ……………………………… 10 Tensleep Sandstone (Pennsylvanian)…………………………………………………… 10 Phosphoria, Park City, and Goose Egg Formations (Permian)…………………………… 10 Dinwoody Formation (Triassic)… ……………………………………………………… 11 Chugwater Group (Triassic)……………………………………………………………… 11 Nugget Sandstone (Jurassic)…………………………………………………………… 11 Gypsum Spring Formation (Jurassic)… ………………………………………………… 11 Sundance Formation (Jurassic)… ……………………………………………………… 11 Traps………………………………………………………………………………………… 15 Seals………………………………………………………………………………………… 17 Resource Assessment…………………………………………………………………………… 17 Assessment Unit 50350101 Tensleep-Park City Conventional Oil and Gas AU… …………… 17 Assessment Results………………………………………………………………………… 18 Acknowledgments… …………………………………………………………………………… 21 References… …………………………………………………………………………………… 21 Appendix A. Input data for the Tensleep-Park City Conventional Oil and Gas Assessment Unit 25

Figures

1. Index map of the Wind River Basin Province, Wyoming… …………………………………… 2 2. Histogram of number of new field wildcat wells……………………………………………… 2 3. Generalized tectonic map of the Wind River Basin Province… ……………………………… 3 4. Structure contour map, top of the Park City Formation… …………………………………… 4 5. Petroleum system events chart Phosphoria Total Petroleum System………………………… 5 6. Columnar section of units in the Phosphoria Total Petroleum System………………………… 5 7. Organic carbon and black shale facies in the Phosphoria Formation………………………… 6 8. Geochemistry of oil… ………………………………………………………………………… 7 9. Fence diagram from northern Utah to the Wind River Basin… ……………………………… 8 iv

10. Timing of oil cracking to gas… ……………………………………………………………… 9 11. Stratigraphic cross section western part of the Wind River Basin… ……………………12, 13 12. Photographs of main reservoir units in the Wind River Basin Province……………………… 15 13. Lithofacies and paleogeography of the Meade Peak Member… …………………………… 16 14. Depth to the top of the Park City Formation… ……………………………………………… 18 15. Plots of grown oil accumulations (fields)… ………………………………………………… 19 16. Depositional environment of hypothesized reservoirs… …………………………………… 20

Table

1. Summary of assessment results for the Phosphoria Total Petroleum System… …………… 20

Plate

1. Stratigraphic cross section showing TPS units in Wind River Basin and Bighorn Basin………… 27 Geologic Assessment of Undiscovered Oil and Gas Resources in the Phosphoria Total Petroleum System of the Wind River Basin Province, Wyoming

By M.A. Kirschbaum, P.G. Lillis, and L.N.R. Roberts

Abstract

The Phosphoria Total Petroleum System (TPS) Conventional Oil and Gas AU total 18 million barrels of oil, encompasses the entire Wind River Basin Province, an area of 294 billion cubic feet of gas, and 5.9 million barrels of natural 4.7 million acres in central Wyoming. The source rocks most gas liquids. likely are black, organic-rich shales of the Meade Peak and Retort Phosphatic Shale Members of the Permian Phosphoria Formation located in the Wyoming and Idaho thrust belt to the west and southwest of the province. Petroleum was Introduction generated and expelled during Jurassic and Cretaceous time in westernmost Wyoming and is interpreted to have migrated The purpose of this study is to assess the potential for into the province through carrier beds of the Pennsylvanian undiscovered oil and gas resources from the Phosphoria Total Tensleep Sandstone where it was preserved in hypothesized Petroleum System (TPS) in the Wind River Basin Province, regional stratigraphic traps in the Tensleep and Permian Wyoming (fig. 1). The TPS approach to resource assessment Park City Formation. Secondary migration occurred during used here is based on defining an area of mature source rock the development of structural traps associated with the and all known and undiscovered reservoirs, and requires an Laramide orogeny. The main reservoirs are in the Tensleep understanding of petroleum generation, trap formation, and Sandstone and Park City Formation and minor reservoirs reservoir seal capacity, which are the primary factors needed are in the Mississippian Madison Limestone, Mississippian- for oil and gas accumulation to exist (Magoon and Dow, 1994). Pennsylvanian Amsden Formation, Triassic Chugwater Group, The petroleum system approach used in this assessment is and Jurassic Nugget Sandstone and Sundance Formation. different from that used in the 1995 assessment in the basin by The traps are sealed by shale or evaporite beds of the Park Fox and Dolton (1996), although the methodology is similar. City, Amsden, and Triassic Dinwoody Formations, Triassic The Tensleep-Park City Assessment Unit (AU) defined here Chugwater Group, and Jurassic Gypsum Spring Formation. corresponds to the Phosphoria Formation-sourced part of the A single conventional oil and gas assessment unit (AU), Basin Margin Subthrust, Basin Margin Anticline, and Deep the Tensleep-Park City AU, was defined for the Phosphoria Basin Structure plays (3501-3503) and to six hypothetical TPS. Both the AU and TPS cover the entire Wind River stratigraphic-trap plays (3506-3513) as defined in the 1995 Basin Province. Oil is produced from 18 anticlinal fields, the assessment (Fox and Dolton, 1996). There have been about last of which was discovered in 1957, and the possibility of 425 new-field wildcats drilled since the last oil discovery in discovering new structural oil accumulations is considered to 1957 and about 275 new-field wildcats drilled since the last gas be relatively low. Nonassociated gas is produced from only discovery in 1965 (fig. 2). No new fields have been discovered, two fields, but may be underexplored in the province. The in the years since the 1995 assessment by Fox and Dolton discovery of new gas is more promising, but will be from (1996). The assessment unit has been evaluated using concepts deep structures. The bulk of new oil and gas accumulations is developed during this and previous assessments in light of any dependent on the discovery of hypothesized stratigraphic traps new advances in the geology of the area and by using analogs in isolated carbonate reservoirs of the Park City Formation. from the Bighorn Basin, Wyoming, and the Paradox Basin, Mean resource estimates for the Tensleep-Park City Colorado, to provide insights into possible undiscovered fields.  Assessment of Undiscovered Oil and Gas in the Wind River Basin Province, Wyoming

110° W 109° W 108° W 107° W 44° N

Park Phosphoria TPS Gas well 20 Phosphoria TPS Oil well Producer from stratigraphically Hot Springs Washakie higher JohnsonTPS Abandoned,Kaycee injection, or other well Teton Dry hole l River Thermopolis Dubois

Powder

26 Wind Wind River n 287 Indian Reservation e Riv 25 e e Boysen r r G Reservoir River

Ocean Lake Bull Lake Natrona Fremont Sublette Riverton 26 20 43° N

Casper Pinedale Lander 189 Platte

351 North MT Jeffrey City 0 15 30 Miles River ID WY 287 Sweetwater Pathfinder WYOMING Reservoir Carbon

Figure 1. Index map of the Wind River Basin Province, central Wyoming, showing boundaries of Phosphoria Total Petroleum System (TPS) and Tensleep-Park City Assessment Unit (AU), (which are coincident, all within red line); Wind River Indian Reserva- tion (gray shaded area); locations of oil and gas wells producing from the Tensleep-Park City Assessment Unit within the Phosphoria TPS and of wells that penetrate all or part of the TPS.

30 558

500 25

400 20

300 15

10 200

5 100 New Field Wildcats (yearly No.) Cumulative New Field Wildcats (No.) 0 0

4 9 4 9 4 9 4 9 4 9 4 9 4 9 4 9 4 9 4 9 4 9 4 9 4 8 8 9 9 0 0 1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8 9 9 0 18 18 18 18 19 19 19 19 19 19 19 19 19 19 19 19 19 19 19 19 19 19 19 19 20 Drilling-Completion Year Figure 2. Histogram of number of new field wildcat wells per year (blue) and cumulative new field wildcat wells (red) for the Tensleep-Park City Oil and Gas Assessment Unit, based on data from IHS Energy Group (2005). Undiscovered Oil and Gas—Phosphoria Total Petroleum System—Wind River Basin 

Structural Geology and northwestern most margin of the Wind River Basin Province. The next thrust system to the northeast includes the Wind Ridge, Coulee Mesa, and Red Grade faults, mapped in The Wind River Basin is surrounded by a series of the northwestern part of the basin (Blackstone, 1990). Another northwest-trending thrust faults and anticlines and several northwest-trending system is the Black Mountain thrust that east-west trending faults (fig. 3). The basin boundaries are terminates or continues on as the Rolff Lake thrust. The defined by uplifts of the Washakie Range and Owl Creek and Rolff Lake thrust can be traced on seismic to the southeast southern Bighorn Mountains to the north, Wind River Range for about 50 mi; the surface expression is a series of hanging to the west, Granite Mountains to the south, and Casper arch wall anticlines consisting of Sheldon, Steamboat Butte, Pilot to the east (fig. 3). The main episode of deformation was Butte, Winkleman Dome, Sage Creek, Lander, Dallas and during the Laramide orogeny (Blackstone, 1990). Derby Domes with a minor southwest offset between Pilot The west margin of the basin is formed by the gently Butte anticline and Winkleman Dome (fig. 3). The next thrust dipping northeast flank of the Wind River Range, which is system to the northeast, called in part the Maverick Springs bounded along its southwest flank by the Wind River thrust thrust, has a surface breakout in the Cody Shale south of (fig. 3). The White Rock thrust (fig. 3) trends to the northwest Maverick Springs anticline (Love and Christiansen, 1985), is out of the Wind River Range bounding the Fish Creek Basin visible on seismic, and is traceable to the southeast for about

110° W 109° W 108° W 107° W 44° N

Wind River Basin Province/50350101 AU Precambrian outcrop Thrust fault T. 45 N. Other fault R. 110W. Washakie Range Anticline R. 105 W. R. 100 W. s n Bighorn Basin i Syncline a 1 3 t R. 95 W. n Plunging fold D 4 u 12 O o w R. 90W. R. 85 W. 6 CR l C M ree n MS k Mo r 5 11 untains o WELL EXPLANATION Fish Creek h g Phosphoria TPS Gas well T. 40 N. RL LD 10 i Basin 2 S 7 T. 40 N. B Phosphoria TPS Oil well

R. 5 W. R. 1 W. P MR Madden anticline Powder R. 1 E. R. 5 E. SB River PB W Casper arch Basin Wind River Range T. 1 N. SC 43° N T. 35 N. CRa T. 35 N. T. 1 S. DB WA RD Mu RH PM L RM CCS CC PS WPS Da BC OM DD 13 BSD W WY in d SF R SM 8 Granite iv T. 30 N. Beaver Divide e T. 30 N. r th B ru 9 st Sp 0 15 30 Miles Mountains

R. 95 W. R. 90 W. R. 85 W.

Figure 3. Generalized tectonic map of the Wind River Basin Province and adjoining areas; primary source of data is Love and Christiansen (1985). Some features dotted where inferred in subsurface. Producing wells from the Phosphoria Total Petroleum Sys- tem (TPS) are shown to help delineate structures. Blue lines are approximate locations of thrust faults determined from 2-D seismic sections; solid at the fault tip; dotted at the hanging wall cutoffs of the Park City. Labeled faults: (1) White Rock thrust; (2) Wind Ridge, Coulee Mesa, and Red Grade thrust system; (3) Black Mountain thrust; (4) Red Creek thrust (Blackstone, 1990); (5) Rolff Lake fault; (6) Circle Ridge/Maverick Springs thrust; (7) Shotgun Butte thrust; (8) Clear Creek fault; (9) Emigrant Trail fault; (10) south Owl Creek thrust fault; (11) north Owl Creek thrust fault; (12) Cottonwood Creek thrust fault; and (13) Casper Mountain fault. Field and anticline abbreviations: B, Bolton Creek; BC, Beaver Creek; BSD, Big Sand Draw; CCS, Casper Creek south; CC, Conant Creek; CR, Circle Ridge; CRa, Clark Ranch; Da, Dallas; DB, Dutton Basin; DD, Derby Dome; D, Dubois; L, Lander; LD, Little Dome; MS, Maverick Springs; Mu, Muskrat; MR, Muddy Ridge; OM, Oil Mountain; P, Pavillion; PB, Pilot Butte; PM, Pine Mountain; PS, Poison Spider; RD, Riverton Dome; RH, Rattlesnake Hills; RM, Rogers Mountain; RL, Rolff Lake; S, Sheldon; SB, Steamboat Butte; SC, Sage Creek; SF, Schrader Flats; SM, Sheep Mountain; Sp, Spindletop; WA, Waltman arch; W, Winkleman; and WPS, West Poison Spider.  Assessment of Undiscovered Oil and Gas in the Wind River Basin Province, Wyoming

35 mi. The structure is defined on the surface by Circle Ridge, north Granite Mountains fault system, which consists of a Maverick Springs, and Little Dome anticlines before passing down-dropped block of Precambrian granite (Love, 1970). The beneath the Wind River Formation and extending to about easternmost northwest-trending structure in the basin is the T. 1N., R. 5E., where the structure apparently dies out. This Casper arch thrust, which bounds the east margin. fault system includes the Pavillion gas field on the hanging Three main east-west-trending structures complete wall. The Maverick Springs trend approximately matches up the main structure of the basin and they include the Granite with the Emigrant Trail thrust system and includes anticlines Mountains, Casper Mountain, and the Owl Creek Mountains. from Riverton Dome (east) in the north to Big Sand Draw These structures follow a different orientation than most other in the south. This fault is projected under the Beaver Divide Wind River Basin structures, and different than Laramide and becomes the southern thrusted margin of the Granite structures in general. Gries (1983) related these different Mountains (Love and Christiansen, 1985). The large Riverton orientations to an overall change in the stress field during the Dome and Beaver Creek fields also have northwest-trending late Laramide. However, Molzer and Erslev (1995) suggested thrust faults that appear on seismic to merge or terminate that the stress field did not change, and at least two of the against the Emigrant Trail thrust (fig. 3). The northwest trend structures, Casper Mountain and the Owl Creek Mountains, continues along the north margin of the Granite Mountains are the result of oblique slip. Stone (2002) also favored in a series of northwest-plunging folds including the Rogers oblique-slip movement, with the structural pattern controlled Mountain/Conant Creek anticlines, the Dutton Basin anticline, by a preexisting Precambrian fabric reactivated during and Rattlesnake Hills anticline (Keefer, 1970). These Laramide compression. structures terminate to the south (figs. 3 and 4) against the

110° W 109° W 108° W 107° W 44° N

Province boundary Edge of contoured area

Structure contour - 5,000 contour interval 1,000 ft Fault, dashed where 0 inferred from seismic data 5,000 0 Pennsylvanian-Permian outcrop

0 5,000 -10,000 -5,000 0 -20,000

5,000 5,000

-15,000 -20,000

-10,000 0

0 43° N 0 -10,000 5,000 -5,000 -15,000 0 0 -5,000 0 0 -5,000 5,000 0 0

5,000 0

5,000 MT 5,000

0 15 30 Miles ID WY

Figure 4. Major structural elements and structure contour map drawn on top of the Permian Park City Formation in the Wind River Basin Province at 1,000-ft contour intervals. Modified from Keefer (1970) and Keefer and Johnson (1993, their pl. 1), supplemented by data from wells drilled since those maps were published and from data gathered from 2-D seismic in the central part of the basin (dashed fault). Undiscovered Oil and Gas—Phosphoria Total Petroleum System—Wind River Basin 

Phosphoria Total Petroleum System evidence that suggest the entire province is part of the TPS. The main pathway for moving the oil from the thrust belt into the Wind River Basin was most likely the Tensleep Sandstone The total petroleum system (TPS) approach defines (Sheldon, 1967; Stone, 1967) although those authors also a mappable pod of mature source rock, all known and considered the possibility of migration in Park City Formation undiscovered reservoirs, and the processes and mechanisms carbonates. There is only limited mixing of Phosphoria- required for oil and gas accumulations to exist (fig. 5) sourced oil with other oil types (see Oil Characterization and (Magoon and Dow, 1994). Phosphoria Formation oils Distribution) probably because of good sealing capacity of produced in the Wind River Basin Province are thought to the rocks between the main reservoir units of this TPS and the have been generated in the Wyoming and Idaho thrust belt next good overlying source rock, the Cretaceous Mowry Shale and then migrated throughout the Wind River Basin (Sheldon, (fig. 6). The main reservoirs are sandstones of the Tensleep 1967; and Stone, 1967). This section of the report provides Sandstone and carbonates of the Park City Formation. 600 550 500 450 400 350 300 250 200 150 100 50 0 Pennsylvanian Mississippian Ordovician Precambrian Devonian Neogene Permian Cambrian Paleogene Silurian Cretaceous Triassic Jurassic GEOLOGIC TIME SCALE Olig Plio PETROLEUM Mio Eoc Pal m m m m e e e e e e e e e e l l l l l l l l l l SYSTEM EVENTS

SOURCE ROCK RESERVOIR ROCK SEAL ROCKS OVERBURDEN ROCK stratigraphic structural TRAP FORMATION oil generation cracking migration to gas GENERATION-MIGRATION-ACCUMULATION

Figure 5. Petroleum system events chart for the Tensleep-Park City Conventional Oil and Gas Assessment Unit. Abbreviations: e, Early; m, Middle; l , Late; Pal, Paleocene; Eoc, Eocene; Olig, Oligocene; Mio, Miocene; Plio, Pliocene.

Petroleum system elements Hiatus

SYSTEM/SERIES ROCK UNIT ERA

Upper (part) Mowry Shale

Shell Creek Shale 1 Muddy Sandstone Main reservoir units Gas Oil Lower Thermopolis Shale Nugget <1% 3% (part) Rusty beds Chugwater <1% <1% CRETACEOUS Cloverly Formation Park City 5.5% 18% Morrison Formation Tensleep 1% 48% Upper Sundance Formation Amsden <1% <1% Gypsum Spring Fm. JURASSIC Middle Madison (excluding Madden) <1% 9% Nugget Ss MESOZOIC (part) Lower ~7% ~79% 1(Includes equivalents and all members that are unequivocally from the unit listed)

TRIASSIC Chugwater Group

Dinwoody Formation Figure 6. Diagrammatic columnar section of the Phosphoria Total Petroleum System Phosphoria Fm Goose (TPS) in the Wind River Basin Province; modified from Fox and Dolton (1996). Lighter Park City Fm Egg Fm PERMIAN Shedhorn Ss shading represents formations that constitute petroleum system elements (source rocks, reservoirs, and seals). Table shows approximate percentages of cumulative oil and gas

PENNSYLVANIAN Tensleep Sandstone production from reservoir units of the Phosphoria TPS relative to total cumulative produc- Amsden Formation tion for all TPSs in the province (data from IHS Energy Group, 2005). The total gas produc- PALEOZOIC (part) MISSISSIPPIAN tion in the basin is about 3.5 trillion cubic feet of gas and about 488 million barrels of oil Madison Limestone (data from IHS Energy Group, 2005). 6 Assessment of Undiscovered Oil and Gas in the Wind River Basin Province, Wyoming

Source Rocks Claypool and others, 1978). Just west of the basin margin near Jackson, Wyoming, the Retort ranges from slightly less than Organic-rich black shales of the Permian Phosphoria 3 to almost 6 weight percent TOC (Hiatt, 1997). Ten samples Formation are thought to be the source for petroleum found in collected from the Phosphoria about 30 to 35 miles east of upper Paleozoic and lower Mesozoic reservoirs of the Wind Lander (figs. 1 and 7), have inorganic carbon contents ranging River Basin (Barbat, 1967; Sheldon, 1967; Maughan, 1984). from 0.41 to 1.48 weight percent (Medrano and Piper, 1995, The black shale facies of the Phosphoria consists of the Meade Conant Creek section) Peak and Retort Phosphatic Shale Members (fig. 7) (Maughan, 1984). Organic carbon averages about 8 weight percent for the Meade Peak in western Wyoming and about 9 weight percent Oil Characterization and Distribution for the Retort in southwestern Montana (Maughan, 1984, his fig. 5). Within the Wind River Basin Province itself, the Oils believed to be derived from the Phosphoria Phosphoria is thin but locally also is rich in organic carbon, Formation have been previously identified and characterized with the Meade Peak containing between < 0.1 to 0.4 percent in the Wind River Basin using bulk properties and molecular total organic carbon (TOC) in three surface samples, and the composition including API gravity, sulfur content, nickel/ Retort containing 1.6 to 2.9 percent TOC in outcrop samples at vanadium values, stable carbon and sulfur isotope composition Stony Point in the western part of the basin (Maughan, 1976; and biomarker composition (Bartram, 1934; Hunt, 1953;

114° 112° 110° 108° 106° 104°

600 kg/m2 (Extent of black shale facies) 46° Thrust belt Butte 0 300 Burial history location 600 1,000 (see fig.10) 3,000 Dillon Billings 5,000 Montana 7,000 Wyoming

44°

Jackson Wind Lander

Pocatello 5,000 River 2,000 9,000 3,000 1000 Idaho 7,000 600 0 Basin 42° 300 Utah

Cheyenne

Salt Colorado Lake City 0 100 40° Miles Denver

Figure 7. Distribution of organic carbon content in the black shale facies of the Phosphoria Formation; modified from Claypool and others (1978). Contour values are determined by multiplying the thickness of black shale facies by the organic carbon content, and that product by the average density of rock, to give a total organic carbon content in kilograms per unit area (kg/m2). The map essentially shows the extent of possible source rocks within the Phosphoria Formation, (primarily in the Meade Peak and Retort Phosphatic Shale Members). Also shown are locations where burial history curves were generated within the province (see fig. 10). Undiscovered Oil and Gas—Phosphoria Total Petroleum System—Wind River Basin 7

Hunt and Forsman, 1957; Brenneman and Smith, 1958; Maturation and Migration McIver 1962; Vredenburgh and Cheney, 1971; Palacas and others, 1994; Silliman and others, 2002). Recent analyses The Phosphoria Formation has long been thought to by the USGS, various scientific reports, and proprietary data have generated petroleum in the Idaho/Wyoming part of the (GeoMark Research, Inc., 2004) were used in the current study thrust belt and the fluids migrated long distances into central to further characterize the Phosphoria-type oil and to map the Wyoming (Sheldon, 1967; Stone, 1967). The black shales extent of the Phosphoria petroleum system in the basin. in the Meade Peak (fig. 9) are thermally mature in much Phosphoria-type oil is distinguished by the high sulfur of western Wyoming and southeastern Idaho (Burtner and content in relation to API gravity (fig. 8A), low stable carbon Nigrini, 1994; Roberts and others, 2004), however, shales isotope values of the saturated and aromatic hydrocarbon in the Retort Member are immature in western Montana fraction (fig. 8B), and low pristane/phytane values (< 1.0). (Claypool and others, 1978). Phosphoria black shales in the High sulfur oil is generated in the Phosphoria Formation western part of the Wind River Basin, although thermally because of Type-IIS kerogen as defined by Orr (1986), based mature (fig. 10), have low TOC content (fig. 7). The timing of on an S/C ratio greater than 0.04 (Lewan, 1985). In general, generation and migration of Phosphoria oil from the Idaho- this oil type is found in Paleozoic to Lower Jurassic reservoir Wyoming border has been proposed to be prior to Laramide rocks; whereas, Mowry oil type, the next younger principal deformation (Cheney and Sheldon, 1959; Sheldon, 1967; oil type in central Wyoming, is found in Upper Jurassic to Stone, 1967; Maughan, 1976; Claypool and others, 1978). Cretaceous reservoir rocks. However, in the southeastern More recently, the Phosphoria is thought to have generated portion of the basin, the Upper Jurassic Sundance Formation petroleum from the Idaho/Wyoming thrust belt and Green is charged with Phosphoria oil at Bolton Creek and Spindletop River Basin, perhaps continuously, through a series of fields, but at Poison Spider field the Sundance reservoir successive events associated with the movement of fluids contains a mixture of Phosphoria and Mowry oils. There are in advance of a sequence of eastward-moving thrust sheets also examples where Mowry oil is present in older rocks— (1) during the Sevier orogeny (Burtner and Nigrini, 1994). Sheldon field (fig. 3), the Lower Jurassic Nugget Sandstone Maughan (1984) showed multiple pathways into the contains Mowry or mixed Mowry-Phosphoria oil types; (2) Wind River Basin from the thrust belt and even from the the eastern part of the basin, the Pennsylvanian Tensleep northern margin of the basin. For a thorough historical Sandstone contains Mowry oil at Pine Mountain; and (3) summary of the migration history see Johnson (2005). on the Casper arch, the Tensleep contains mixed Mowry- Conduits for the long distance migration of the petroleum Phosphoria oil at Clark Ranch field (fig. 3) and Notches field, generated from the Phosphoria are hypothesized to include the which is located east of the province boundary on the Casper continuous eolian sandstones of the Tensleep Sandstone (fig. arch. 9) and marine carbonates of the Park City Formation (Sheldon,

A. 5.0 B. 10 Waltman Waltman 4.5 Cretaceous 9

) Cretaceous Phosphoria mix T 4.0 8 Phosphoria mix N Phosphoria

E Phosphoria

C 3.5 7 R E RATIO E N P

3.0 A 6 T T H 2.5 Y H

G 5 I P E /

W 2.0 4 E ( N R

1.5 A

U 3 T F S I L

1.0 R

U 2 P S 0.5 1

0.0 0 0 10 20 30 40 50 60 -32 -31 -30 -29 -28 -27 -26 -25 -24 API GRAVITY (DEGREES) 13

Figure 8. A, Plot of API (American Petroleum Institute) gravity versus sulfur content for oil samples from the Wind River Basin; Phosphoria oils contain moderate to high sulfur content (greater than 0.5 percent) as a function of API gravity. B, Plot of dC13 aromatic hydrocarbons versus pristane/phytane of oils from the Wind River Basin. Phosphoria oils have pristane/phytane values less than one; whereas, Cretaceous oils and Phosphoria-Cretaceous mixed oils have pristane/phytane values greater than one. Data are in part from and used with the permission of GeoMark Research Inc. (2004). 8 Assessment of Undiscovered Oil and Gas in the Wind River Basin Province, Wyoming

upper member Red Creek Tosi Chert Tongue lower member

Togwotee Pass Retort PhosphaticUPPER TONGUEGros Shale Tongue Ventre slide Hungry Creek Fall Creek Rex Chert Dinwoody Lakes Member lower tongue Bull Lake Fort Franson Hall Tongue Ervay lower chert Member member Retort Phosphatic Conant Shale Tongue Creek Tosi Chert Tongue cherty shale member Sublett Range Meade Peak Grandeur Phosphatic Shale Tensleep Tongue Member Formation (part)

114° 110° 106° Phosphoria Shedhorn Fm Ss MT Rex Chert WY Member Phosphorite and mudstone Sandstone 44° Wind River Basin Park City Line of Cherty mudstone Fm section

Wells ID Chert Carbonate rock Formation (part) UT (Pennsylvanian) Wells/Tensleep Grandeur Tongue WY Ss Greenish-gray shale CO

40° Sandstone

Figure 9. Segment of fence diagram modified from McKelvey and others (1959), extending from northern Utah into the western part of the Wind River Basin. Shown are distribution and relative thicknesses of various units in the Permian Phosphoria Formation and equiva- lent strata and the upper part of the Pennsylvanian-Permian Wells and Tensleep Sandstones.

1967; Stone, 1967). In light of the more discontinuous nature been filled by juxtaposition across the thrust faults. Oil pools of the Park City carbonates (plate 1), the more likely main trapped and preserved in the deepest parts of the basin during carrier bed was the Tensleep Sandstone. Fluids involved in the remigration most likely have been cracked to gas (fig. this initial migration are interpreted to have been trapped in 10). We use the maturation and migration model presented regional stratigraphic traps and sealed updip toward the east to explain the presence of Phosphoria-type oil in many fields side of the area now occupied by the Wind River Basin, by producing from Permian and Pennsylvanian strata, as well as evaporites of the Goose Egg Formation, which is a facies from other reservoirs in some fields, in the Phosphoria TPS in equivalent of the Phosphoria and Park City Formations (Stone, the Wind River Basin Province. 1967). Keefer (1969) presented evidence that the horizon marking the Phosphoria-Tensleep contact in the Wind River Basin Province dipped to the west and southwest across the Stratigraphic Units and Reservoir Rocks basin, which could have allowed migration of oil updip across the Casper arch and into a stratigraphic trap along the ancestral Pathfinder uplift (Mallory, 1967, his fig. 2; Mallory, 1972, p. 119). These accumulations are proposed to have remained Madison Limestone (Mississippian) intact within the Tensleep Sandstone and Park City Formation until Laramide structures formed in latest Cretaceous time The Madison Limestone consists of 600 to 700 ft of and there was remigration of petroleum into these structures. carbonate strata in the western and northwestern parts of the Reservoirs stratigraphically below the Tensleep may have Wind River Basin, but thins to about 300 ft at the southeast Undiscovered Oil and Gas—Phosphoria Total Petroleum System—Wind River Basin 9

Age (Ma)

Timing of oil 90 80 70 60 50 40 30 20 15 10 0 generation (hypothetical) Shell 33X-10 Start of oil No gasNo gas Peak oil End of oil Amoco Unit 100 Timing of oil cracking to gas No gasNo gas Start of gas Peak gas Bighorn 1-5 End of gas Minor generation may continue Adams OAB 1-17

Epochs Post-Miocene Miocene Hells Half Acre Oligocene Eocene Paleocene West Poison Spider Late Cretaceous No gasNo gas

90 80 70 60 50 40 30 20 15 10 0 Late Cretaceous Paleocene Eocene Oligocene Miocene

110° W 109° W 108° W 107° W 44° N

Bighorn 1-5

Shell 33X-10

Adams OAB 1-17 Hells Half Acre 43° N Explanation Burial history locations Amoco Unit 100 Wind River Basin Province boundary West Poison Spider

MT 0 15 30 Miles ID WY

Figure 10. Plot showing timing of hypothetical oil generation from Type-IIS source rocks of the Meade Peak and Retort Phosphatic Shale Members of the Phosphoria Formation in the Wind River Basin Province. Timing of cracking to gas also is shown for hypothetical oil generated in the province and for Phosphoria-sourced oil that migrated into the province and was trapped in reservoirs of the Park City and adjacent formations. Vertical dashed line at 15 Ma represents beginning of major regional uplift, erosion, and subsequent cooling. corner (Keefer and Van Lieu, 1966). In the Bighorn Basin to uppermost sequence at Madden field in the northeastern the north, Sonnenfeld (1996) defined six 3rd order carbonate Wind River Basin (fig. 3) is extensively brecciated limestone, sequences deposited in outer ramp to supratidal depositional making an effective seal for the lower sequences according settings. Sequences are bounded by subaerial exposure to Westphal and others (2004). Tight lithologies at sequence surfaces at five of the six boundaries, the uppermost by an boundaries act as flow barriers (Westphal and others, 2004). extensive karst zone and associated breccia. Westphal and The Madison is a minor reservoir in the Phosphoria TPS, others (2004) concluded that variations in reservoir quality contributing 9 percent of the oil in the province (fig. 6). Gas are the result of a combination of (1) facies control, (2) a produced from the Madison at Madden field is considered to diagenetic overprint by dolomitization, and (3) a late stage be sourced from the Cretaceous-Lower Tertiary Composite hydrothermal brecciation and cementation by calcite. The TPS (Johnson and others, chapter 4, this CD-ROM). 10 Assessment of Undiscovered Oil and Gas in the Wind River Basin Province, Wyoming

Amsden Formation (Mississippian and Tensleep and is thought to enhance permeability, but also Pennsylvanian) creates additional heterogeneity and may complicate flow units (see discussion of separate oil/water contacts in fractures The Amsden Formation consists of three major units and matrix in Hurley and others, 2003). Internal poikolitic in the Wind River Basin, in ascending order the Darwin dolomite cements in selected intervals of sandstone are less oil Sandstone, Horseshoe Shale, and Ranchester Limestone stained. Dolomitic sandstone of probable sabkha and marine Members (fig. 11; Sando and others, 1975); aggregate (?) depositional environments are tight and are not oil stained. thicknesses range from about 100 ft to nearly 400 ft (Keefer The Tensleep is the most important reservoir in the and Van Lieu, 1966). The formation unconformably overlies a Phosphoria TPS as measured by the number of wells partially karsted surface at the top of the Madison Limestone completed (> 500) and by the volume of oil produced, which (Sando and others, 1975) and conformably underlies the is about 237 MMBO according to IHS Energy Group (2005), Tensleep Sandstone. The Amsden and Tensleep are mapped or about 48 percent of the total oil produced in the Wind River as a single unit in some areas (Keefer and Van Lieu, 1966). Basin Province from all reservoirs (fig. 6). An isopach map of the Darwin Sandstone Member shows a relatively sheetlike distribution, and the Darwin is thought to have been deposited by fluvial and marine processes. However, Phosphoria, Park City, and Goose Egg Formations cross sections of the Darwin show distinct thin areas within (Permian) the unit that were interpreted to be islands during deposition (Sando and others, 1975, p. 21, their plate 2). An alternate Permian strata, ranging in thickness from 200 to 400 ft hypothesis could be incised valleys into the Madison that were (Keefer and Van Lieu, 1966), are composed of three laterally filled with a variety of lithologies. In one core examined at the equivalent formations, each representing a distinct facies USGS core library in Denver, Colorado, (core identification in different parts of the Wind River Basin: (1) Phosphoria number D380), the Darwin consists of crossbedded sandstone Formation, consisting of chert, cherty shale, and phosphatic with pin-stripe lamination and thin carbonates with salt ridge shale at the west margin (Maughan, 1984), (2) Park City structures that are interpreted as eolian dune and sabkha Formation, consisting of carbonates and shale across the deposits. The Darwin Sandstone is a minor reservoir in the central part (figs. 12 B and C), and (3) Goose Egg Formation, basin; most of the reported Amsden production is apparently consisting of green and red shale and evaporites in the from this member based on perforated zones reported in IHS eastern part (fig. 13). There was an overall transition from Energy Group (2005). open marine settings (Phosphoria, main source rock), to shallow water carbonates (Park City, main reservoir rocks), to evaporites (Goose Egg, lateral seal) from west to east across Tensleep Sandstone (Pennsylvanian) Wyoming during Permian time (fig. 13; Maughan, 1984; and Piper and Link, 2002). As previously discussed in the section The Tensleep Sandstone is about 250 to 400 ft thick (fig. on source rocks, two shale units of the Phosphoria Formation 11; pl. 1) in the Wind River Basin. The Tensleep consists in areas mainly west of the Wind River Basin — Meade Peak primarily of eolian sandstone (fig. 12A), but also contains and Retort Phosphatic Shale Members — are the main source minor dolomitic sandstone and dolostone (USGS core A693; rocks of the TPS. Carr-Crabaugh and Dunn, 1996). In the Sand Draw field, The Park City consists, in ascending order, of the the Tensleep is composed predominantly of crossbedded Grandeur, Franson, and Ervay Members. The Park City sandstone, much of it over-steepened, and is oil stained in consists of carbonate mudstone, wackestone, packstone, core (see USGS core A693). An overlying transition zone is grainstone, rudstone, and conglomerate and some non- tightly cemented with carbonate, has no oil stain, and is the carbonate siltstone, sandstone, green dolomitic shale, and seal for the reservoir. The sandstones are carbonate cemented chert (figs. 12 B and C) (Whalen, 1996). In the Bighorn Basin, in this core. Regionally, the Tensleep is cemented by quartz the best reservoirs are in lower intertidal dolomite boundstone overgrowths and (or) carbonate (Fox and others, 1975). that exhibit well-connected fenestral pore space (Coalson Porosity ranges from about 5 to 22 percent and permeability and Inden, 1990). Peterson (1984) cites the Ervay Member ranges from 0.1 to 100 millidarcies (Fox and others, 1975, as being the most productive of the Park City carbonate units their fig. 7). Porosity decreases with depth and is generally because the unit was deposited as large carbonate banks, less than 8 percent below 10,000 ft (Fox and others, 1975). A the Ervay is underlain and intertongues with the organic study of the internal facies in the Bighorn Basin shows the best rich Retort Phosphatic Shale Member, and is the highest porosity and permeability in eolian facies and the poorest in stratigraphic unit within the Park City and occupies the highest regionally extensive dolomitic sandstones (Hurley and others, structural position in many traps. 2003). These dolomitic sandstones are referred to as marine The Park City is the second most important reservoir in dolostones and are thought to be vertical permeability barriers, the TPS contributing about 5.5 percent of the gas and about 18 unless fracturing is present (Carr-Crabaugh and Dunn, 1996). percent of the oil produced in the Wind River Basin Province Fracturing is an important component to fluid flow in the from reservoirs in all TPSs (fig. 6). Undiscovered Oil and Gas—Phosphoria Total Petroleum System—Wind River Basin 11

Dinwoody Formation (Triassic) Fluvial deltaic siltstones and sandstones of the Jelm The Dinwoody Formation consists of 50 to 200 ft of Formation and lacustrine mudstones and carbonates of the calcareous shale, siltstone, and sandstone with interbedded Popo Agie Formation are not reported to be reservoirs in the thin limestone and red mudrock (Keefer, 1969) and lies province. unconformably on Permian rocks (Paull and Paull, 1986, 1987). Picard (1993) described the Dinwoody to be mostly composed of gray, green, light brown or orange siltstone with Nugget Sandstone (Jurassic) dolomite cement. The siltstone has minor sand, clay, and mica and is interbedded with anhydrite in the subsurface or The Nugget Sandstone consists of crossbedded to rippled with gypsum in some surface exposures. Picard (1993) also sandstone and minor continuous siltstone beds; it reaches a observed that the Dinwoody has higher resistivity on well logs thickness of about 500 ft, but thins to zero at the east margin than the overlying Chugwater rocks. Stone (1967) stated that of the Wind River Basin (Keefer, 1969). At Derby Dome the Dinwoody in the Bighorn Basin has little or no reservoir (fig. 12 D) it contains crossbedded sandstone of eolian origin porosity and the little production reported from the unit is and irregular bedded units of sabkha origin. The Nugget probably from the upward movement of petroleum through produces oil and associated gas mainly at Steamboat Butte and fractures in the crests of anticlines. In the Wind River Basin, Winkleman fields, and also at Riverton east, Riverton Dome only small amounts of oil are reported from the formation east, and Sheldon fields. Cumulative totals are only about 15 (IHS Energy Group, 2005). million barrels of oil and 16 to 17 billion cubic feet of gas (Wyoming Geological Association, 1989; IHS Energy Group, 2005). Chugwater Group (Triassic)

The Chugwater Group, ranging in thickness from 1,000 Gypsum Spring Formation (Jurassic) to 1,300 ft (Keefer, 1969), consists, in ascending order, of the Red Peak Formation, the Alcova Limestone, the Crow The Gypsum Spring Formation consists of gypsum (or Mountain Sandstone, and the Jelm or Popo Agie Formations. anhydrite in the subsurface), red shale and siltstone, and thin With the exception of the Alcova, which is a marine limestone, limestone and dolomite beds (fig. 12 D) (Sharkey, 1946; the remainder of the Chugwater Group is mainly red mudrock Imlay, 1980). The Gypsum Spring is as much as 250 ft thick in interbedded with very fine to medium-grained sandstone the western two-thirds of the Wind River Basin, but is absent (Keefer, 1957; Tohill and Picard, 1966; Picard, 1993). The in the eastern one-third (Keefer, 1969). The Gypsum Spring Crow Mountain is thought to be of tidal flat to shallow marine does not produce petroleum in the province. However, the origin (Tohill and Picard, 1966). most important feature of this unit, in terms of the petroleum The Red Peak consists of silty claystone to sandstone system, is the presence of extensive anhydrite beds within and has casts of salt, mud cracks, and raindrop impressions, the lower part of the unit that exceed 100 ft in thickness and indicating tidal flat to nearshore marine depositional apparently are continuous over much of the western part of environments (Picard, 1993). The origin of other units, the province (fig. 12). This anhydrite unit should create an consisting of remarkably continuous sandstone or claystone effective seal for underlying reservoirs, except where breached units, is much less certain (Picard, 1993; J.D. Love, oral by faults. commun., cited in Johnson, 1993). However, continuous sandstones observed near Alcova Reservoir have irregular bedding that may be sabkha related. Other units exposed near Sundance Formation (Jurassic) Dubois, Wyoming, have distinct channel forms. The Alcova Limestone consists of marine limestone and The Sundance Formation, 200 to 550 ft thick, consists of dolomite and contains minor mollusks and abundant algal interbedded sandstone and siltstone, with some limestone and structures (Picard, 1993). The unit is a minor reservoir that shale, that were deposited in marine to eolian environments produces from fractured limestone with no primary porosity (Keefer, 1969; Picard, 1993). Some strata are glauconitic at Big Sand Draw field (Wyoming Geological Association, and highly fossiliferous. The unit may be effectively sealed 1989). off from Phosphoria-generated oil in the western half of The Crow Mountain Sandstone is characterized by fine- the Wind River Basin by anhydrite beds in the underlying to medium-grained crossbedded sandstone (Picard, 1993). The Gypsum Spring Formation. About 3.5 million barrels of oil unit produced about 2 million barrels of oil with associated gas has been produced from the Sundance at Bolton Creek, Poison in the Beaver Creek, Pilot Butte, Poison Spider, Rolff Lake, Spider, Schrader Flats, and Spindletop fields (IHS Energy Sheldon northwest, and Steamboat Butte fields (IHS Energy Group, 2005), all located at the extreme eastern margin of the Group, 2005). The Crow Mountain is a minor reservoir in the province where the Gypsum Spring anhydrite beds are not province. present. 12 Assessment of Undiscovered Oil and Gas in the Wind River Basin Province, Wyoming Undiscovered Oil and Gas—Phosphoria Total Petroleum System—Wind River Basin 13

currently NW injection well SE 1 2 3 4 5 6 Spread Creek Wildcat Wildcat Steamboat Butte Field Wildcat Big Sand Draw Field Lower Slide Lake W.A. Moncrief JR Helmerich and Payne Marathon Oil Company BP America Nance Petroleum Corporation measured sections (Equitable) 1-16 Tribal (Gulf Oil) Production Company (Sinclair) sec 34, 35, T. 43 N., R. 114 W. Lava Mountain 13-36 sec. 16, T. 5 N., R. 5 W. Tribal C-28 (Pan American) Big Sand Draw Unit 18 sec. 5, T. 42 N., R. 114 W. sec. 36, T. 43 N., R., 110 W. 6,442 KB sec. 32, T. 4 N., R. 1 W. Tribal-M 1 sec. 10, T. 32 N., R. 95 W. sec. 8, T. 39N., R. 112 W. 9,256 GR API 4901320851 5,721 KB sec. 4, T. 2 S., R. 6 E. 5,956 GR (from Love and others, 1951) API 4901321657 API 4901321081 5,596 KB API 4901305500 API 4901360095 Cumulative Production (WOGCC, 2005) Cumulative Production (WOGCC, 2005) reported as Tensleep Sandstone; Tensleep Sandstone plots in Amsden Formation 245,313 B0 271,415 BO 19,472 MCFG 44,176 MCFG 5,157,578 BW 30,159,402 BW Perf. 6722-6730 Perf. 7531-7604 depth corrected GR R Jgs (WOGCC, 2005) may be over thickened using best fit due to structural dip to stratigraphy Jn (WOGCC, 2005) 5 to account for structural dip GR S GRR GR R Sundance Formation 2 gypsum at base Gypsum Spring Formation GR R Nugget Sandstone 5 7

Popo Agie Formation Jelm and Popo Agie 8 (member in Love and others, 1951) Formations undivided

Crow Mountain Sandstone Alcova Limestone (member in Love and others, 1951)

6

8 Chugwater Group Red Peak Formation 3 (member in Love and others, 1951)

6

9

9 Dinwoody Formation

cherty phosphatic shale Phosphoria and Park City Formations 7 datum chert pebbles

Tensleep Sandstone 4

7 Ranchester Limestone Member Amsden Formation Horseshoe Shale Member 10 Darwin Sandstone Member

cherty Figure 11.—Stratigraphic 8 cross section of upper cherty and lower Mesozoic units Madison Limestone oriented northwest to south- east across the western part of the Wind River Basin and 8 extending westward into Core is available for this well at the Core is available for this well at the USGS USGS core library, Denver, Colo. core library, Denver Colo. Identification Fish Creek Basin (see fig. 3). Identification number S813. number A693 with thin sections. 18 mi 36 mi 25 mi 43 mi 7 mi 1 Assessment of Undiscovered Oil and Gas in the Wind River Basin Province, Wyoming

110° W 109° W 108° W 44° N 107° W R. R. R. R. 110 100 90 80 T. 45 N. W. W. W. W.

14 15 1 2 13 L Thermopolis Wind River L Dubois 10 11 12 Basin Province T. 40 N. 3 9 (Madison Plate 1 Limestone) 8 4

7 T. 1 N . 43° N T. 35 N. T. T. 1 1 T. 1 S. W. E. 5 L Pinedale L Lander 6 T. 30 N. 0 15 30 Miles Jeffrey City L

EXPLANATION Generalized depositional environments Header Predominantly marine limestone or dolomite Lander field Oil or Gas Field Dry Hole Predominantly eolian sandstone. Gas well

Injection well Continental or marginal marine mudrock and sandstone Moncrief Operator Tribal 1 Lease name and well number sec. 1, T. 1 N., R.111 W. Location (section, township, range) Marine shale 6,000 ft GL GL, Ground Level; KB, Kelly Bushing API 4901300000 API number marker horizon

Cumulative Productiom (WOGCC, 2005) Tensleep Sandstone Abbreviations: Perf., interval of initial 2,212 MCF production or perforated zone in feet; 1,274 BO MCFG, thousands of cubic feet gas; 4,615 BW BO, barrels of oil; BW, barrrels of Perf. 1,000-1,050 Figure 11. Explanation and index map for figure 11 A; map also water. Geophysical log shows location of cross section presented in plate 1. Datum is top of Tensleep Sandstone. Well depths are in thousands of feet. GR R Perforated interval shown in Abbreviations: Jgs, Gypsum Spring Formation; Jn, Nugget Sand-

2700 red. A representation of the grain size is shown to the right stone. See figure 6 for stratigraphic chart.—Continued of the depth column. Note that the grain size depths may not correspond to the drillers’ cored depth.

2800 Abbreviations: GR, Gamma ray; R, Resistivity; S, Sonic

18 mi Distance in miles between projection of well into line of section Undiscovered Oil and Gas—Phosphoria Total Petroleum System—Wind River Basin 1

A. D. Park City Formation

Gypsum Spring Formation

Nugget Sandstone Tensleep Sandstone

Ps B. C. Ppc

Ps

Park City Formation

Ppc

erosion surface

erosion surface PPt

Figure 12. Photographs of main reservoir units in the Wind River Basin Province: A, view is mainly of the Tensleep Sandstone, overlain by the Park City Formation at Sinks Canyon. Indented part of outcrop (arrow) is a carbonate bed within the Tensleep that is about 20 feet thick. B, roadcut at Stony Point, located about 6 miles northwest of Dubois, Wyoming, (fig. 1) along U.S. Highway 287/26, showing upper- most Pennsylvanian to Permian Tensleep Sandstone, PPt; Permian Park City Formation, Ppc; and part of Permian Shedhorn Sandstone (?), Ps. The lower erosion surface appears to be within the Tensleep, but is defined as the base of the Park City (Keefer, 1957, p. 174). The beds above the lower erosion surface consist of chert pebbles and convolute-bedded fine-grained sandstone of fluvial (?) origin overly- ing upper fine-grained crossbedded sandstone of eolian (Tensleep) origin. The Park City consists of grainstone, cherty limestone, and thinly laminated phophorite (Keefer, 1957). The Shedhorn consists of fine- to medium-grained, well rounded, crossbedded sandstone of possible eolian origin. C, carbonates of the Park City Formation at Sinks Canyon, located a few miles southwest of Lander (see fig. 1). D, exposures of Nugget Sandstone and Gypsum Spring Formation near Derby Dome in the southern part of the Wind River Basin (fig. 3). The Nugget consists of interbedded medium-grained crossbedded sandstone of eolian origin and fine-grained, irregularly bedded sand- stone of sabkha origin. The Gypsum Spring consists of red mudrock, bedded gypsum, and minor laminated carbonate. Note the vehicles in the far right center of the photo for scale. Traps

As mentioned previously, oil sourced from the organic- both basins. Some of the traps also may have been related rich shales in the Phosphoria Formation are interpreted to have to the Pathfinder uplift, a poorly understood paleostructure first accumulated in large stratigraphic traps that extended that formed in Pennsylvanian time in the southeastern part of from the Bighorn Basin south into the Wind River Basin the Wind River Basin (Mallory, 1967, 1972). Some traps in (Sheldon, 1967; Stone, 1967). With respect to the Park City the Wind River Basin were possibly created in the Tensleep Formation, possible traps were related to facies change from Sandstone beneath an unconformity-forming paleotopography carbonates into evaporites of the Goose Egg Formation in (fig. 12B, lower erosion surface) caused by truncation in the 16 Assessment of Undiscovered Oil and Gas in the Wind River Basin Province, Wyoming

LITHOFACIES - MEADE PEAK AND EQUIVALENTS Organic-rich mudstone Poorly known; mixed clastics and carbonate (?) Carbonate Halite Sandstone Gypsum Interbedded dolomite-siltstone Red mudstone

Unconformity, Land (?) ND SD

MT WY

NB location of thrust belt UT

CO

0 100 200 300 MILES

116° 114° 102° 112° 110° 108° 106° 104°

48° Williston Basin

46° ND Butte

Ocean Current SD Milk River Dillon Uplift MT WY Trade Winds Powder River

44° Trough

l

l

Jackson i s

n

Oquirrh-Wood i

s Phosphoria Basin a

River-Sublet b Goose r e

Basin Pocatello t NB

n

i

d n

a Egg

42° h

g

i

h

n UT r Rock Springs o Basin h g i B

Emergent Antler Highland Paleolatitude 10° N Salt Lake City CO FrontAncestral Range 40°

0 100 200 300 MILES

Figure 13. A, lithofacies of Meade Peak Phosphatic Shale Member of the Phosphoria Formation and equivalent rocks in Wyoming and adjacent areas from Maughan (1984). B, generalized paleogeographic reconstruction of the Meade Peak, based on Maughan (1984), Peterson (1988), and Piper and Link (2002). Area of Wind River Basin Province outlined in red. Undiscovered Oil and Gas—Phosphoria Total Petroleum System—Wind River Basin 17

Bighorn Mountains area (Simmons and Scholle, 1990) and in Resource Assessment the southeastern Wind River Basin (Keefer, 1969). Remigration of the oil out of the stratigraphic traps took place during the Laramide orogeny, between the Late The Phosphoria TPS consists of one AU in the Wind Cretaceous and middle Eocene, when major compressional River Basin Province. Maximum depths to the main reservoirs structures were created concomitant with formation of the (Park City and Tensleep) exceed 25,000 ft (fig. 14). Depths to Wind River Basin. There are three main types of structures: producing reservoirs in the main fields of this TPS are reported (1) basin-bounding faults including the Wind River thrust, to range from about 200 ft to more than 12,000 ft (IHS Energy located along the southwest margin of the Wind River Range Group, 2005). Existing fields generally report well-established (fig. 3); the Granite Mountains structure; the Casper arch; and oil/water contacts (Wyoming Geological Association, 1989) the Owl Creek Mountains; (2) major thrust splays, mainly and well-defined traps, which are normally associated with off the Owl Creek Mountains (Blackstone, 1990); and (3) discrete conventional accumulations. The petroleum system through-going southeast-northwest-trending thrust faults. is an oil province, however, in the future there may be more Most of the oil and gas production from Phosphoria source potential for gas production. The AU, which covers the entire rocks in the Wind River Basin Province comes from structural province, is an area of about 4.7 million acres. The surface traps in the form of hanging wall anticlines along these ownership consists of about 1.9 million acres of Federal lands, through-going southeast-northwest-trending thrust systems about 1.4 million acres of private lands, 1.1 million acres of (fig. 3). Native American lands, and about 0.3 million acres of State Although there is considerable uncertainty, there may lands. be potential undiscovered resources from stratigraphic traps in the Park City Formation. On the east side of the Bighorn Basin, the Cottonwood field is a stratigraphic trap, in which Assessment Unit 50350101 Tensleep-Park City the Ervay Member of the Park City Formation produces from Conventional Oil and Gas AU intertidal dolomitic boundstones and to a lesser extent from intertidal to supratidal dolomites (Coalson and Inden, 1990). The Tensleep-Park City Conventional Oil and Gas These intertidal facies also are present in the Ervay, as well as AU consists of oil and gas trapped mainly in reservoirs of in a lower unit, the Franson Member, in a north-south trending the Tensleep Sandstone and Park City Formation. The AU continuous band across the Wind River Basin (Ahlstrand has 18 oil fields over the minimum size of 0.5 MMBO (fig. and Peterson, 1978). However, detailed correlations (pl. 1) 15A) and two gas fields over the minimum size of 3 BCFG indicate a low degree of continuity in individual carbonate (NRG Associates, 2005). The Beaver Creek oil and gas beds. Areal extents of the boundstone deposits are on the field did not have data available for calculating an estimated order of 160-500 acres that may coalesce over an area of ultimate recovery (fig. 15A), but has individual wells where about a township (Coalson and Inden, 1990). The presence of the production to date exceeds the minimum field size boundstone is used as evidence for the presence of a paleohigh (Wyoming Oil and Gas Conservation Commission, 2005). in the Riverton Dome area (Estes-Jackson and others, 2000). All the discovered fields are from hanging wall anticlines associated with thrust systems within or at the edge of the province. The first oil field was discovered in 1886 and there Seals has not been a new discovery since 1957 (fig. 15A, C). The two gas fields were discovered in the early 1960s. Most of The Phosphoria TPS is separated in large part from the the production is from shallow reservoirs, but reservoirs have overlying Cretaceous-Lower Tertiary Composite TPS over been found as deep as 11-12,000 ft (fig. 15C). The estimated much of the basin. There is small amount of leakage in a few ultimate recovery for individual fields ranges from 0.9 to 117.9 cases. The probable main regional seal in the western part MMBO. The fact that no new oil field has been discovered of the basin is formed by the extensive anhydrite beds in the since 1957 and no new gas field since 1965 does not bode well Gypsum Spring Formation (figs. 11, 12D). This formation for future success in this petroleum system unless a new play is absent in the eastern part of the basin, however, possibly concept can be determined. Future success also is pessimistic allowing more leakage especially in the Casper arch area. when viewed in terms of new field wildcats that penetrate the Local seals in addition to the Gypsum Spring, include shale TPS. About 150 new field wildcats were drilled before the and anhydrites in the Park City, Dinwoody, and Chugwater last oil field was found (fig. 15B) and since then about 425 Formations, and possible diagenetic seals in the Park City new field wildcats have been drilled with activity tailing off (Coalson and others, 1994) and Madison Limestone (Westphal precipitously during the last decade (fig. 2). and others, 2004). Undiscovered traps may still exist, however, in deep untested structures in the basin interior; such accumulations would most likely be gas-prone based on thermal maturity, but a few may contain oil. The main basis for estimating the discovery of as many as 15 oil accumulations and 40 gas 18 Assessment of Undiscovered Oil and Gas in the Wind River Basin Province, Wyoming

110° W 109° W 108° W 107° W 44° N

Depth, in feet, to top of Park City T. 45 N. 0-5,000 R. 110 W. R. 105 W. 5,000-10,000 10,000-15,000 15,000-20,000 20,000-25,000 >25,000

T. 40 N. T. 40 N. R. 5 W.

R. 1 W. R. 1 E. R. 5 E.

T. 1 N. 43° N T. 35 N. T. 35 N. T. 1 S.

Wyo. R. 95 W. R. 90 W. R. 85 W.

Province

Penn/Perm outcrop T. 30 N. T. 30 N. Margin of Permian rocks or limit of mapped structure from Keefer, 1970 0 15 30 Miles

Figure 14. Depth to the top of the Park City Formation, contour interval 5,000 feet (available in the ArcGIS project at a contour interval of 1,000 feet). The map was created by subtracting the structure contour map of the top of the Park City (fig. 4) from a digital elevation model of the Wind River Basin Province.

accumulations (see Appendix A) within the Wind River Basin The sizes of undiscovered fields were determined on the Province, comes from potential stratigraphic traps in the Park basis of analogies with stratigraphic traps in the Permian Park City Formation in the form of algal mounds or islands (fig. City Formation in the Bighorn Basin and the Pennsylvanian 16) similar to those interpreted in the Bighorn Basin (Coalson Paradox Formation in the Paradox Basin. The median of and Inden, 1990), as well as in the Paradox Basin of Colorado 1.5 MMBO was estimated from typical fields in carbonate (Chidsey and Eby, 2004). This concept is similar to that buildups in the Paradox Formation, which range from about described by Fox and Dolton (1996), but the current assessment 0.7 to 2 MMBO (Chidsey and Eby, 2004). The maximum uses a model of a shallow water sill (Piper and Link, 2002) that field size of 50 MMBO was conservatively reduced from allowed buildups similar to the small, 0.7 to 2 MMBO, fields of cumulative production at Cottonwood field in the Bighorn the Paradox Basin (Chidsey and Eby, 2004). Basin, which has produced about 65 MMBO (Wyoming Oil Other possible stratigraphic traps may be present in and Gas Conservation Commission, November, 2005). The the Tensleep, as the result of being truncated beneath an gas median and maximum numbers were derived by using the unconformity along the edge of the ancestral Pathfinder uplift gas equivalents of the oil accumulations. (approximately at the edge of the Granite mountains, see Mallory, 1967, 1972); historically, however, many tests have been made in this area without success (fig. 3). There also may be some potential in facies pinchouts of the Shedhorn Sandstone, Assessment Results a clastic (eolian ?) unit equivalent to the Phosphoria Formation in the northwestern part of the Wind River Basin (fig. 9), as well Undiscovered oil fields in the Tensleep-Park City as hypothesized facies pinchouts within the Darwin Sandstone Conventional Oil and Gas AU are estimated to contain means where the Darwin fills irregularities in the upper surface of the of 18 MMBO, 19 BCF of associated gas, and 0.4 MMB of Madison Limestone in a way similar to the Cretaceous Muddy associated natural gas liquids (table 1). Undiscovered gas Sandstone, which is a prolific oil producer in the basin (see cross fields are estimated at the mean to be 275 BCFG and 5.5 sections of Sando and others, 1975, their pl. 2). MMB of natural gas liquids (table 1). Undiscovered Oil and Gas—Phosphoria Total Petroleum System—Wind River Basin 19

A. 100

(1886) 10

GROWN OIL- ACCUMULATION SIZE (million (1957) barrels of oil)

1

0 1880 1905 1930 1955 1980 2005 ACCUMULATION-DISCOVERY YEAR

B. 100

10

GROWN OIL- ACCUMULATION SIZE (million barrels of oil)

1

0 0 100 200 300 400 500 600 CUMULATIVE NEW-FIELD WILDCAT WELLS (No.)

C. 0

2,000

4,000

RESERVOIR 6,000 DEPTH, OIL ACCUMULATIONS (feet) 8,000

10,000

12,000

14,000 1880 1905 1930 1955 1980 2005 RESERVOIR-DISCOVERY YEAR

Figure 15. A, plot showing size of grown oil accumulations (fields) relative to discovery year for the Park City-Tensleep Conventional Oil and Gas Assessment Unit 50350101. Data from NRG Associates (2005). Grown accumulations refer to the estimated ultimate recovery of a field. B, plot showing size of grown oil accumulations relative to the number of cumulative new field wildcat wells (data from IHS Energy Group, 2005). There are 558 new field wildcats drilled in this assessment unit (see fig. 2). Grown accumulations refer to the esti- mated ultimate recovery of a field. C, plot showing reservoir depth of oil accumulations relative to reservoir discovery year for the Park City-Tensleep Conventional Oil and Gas Assessment Unit. Data from NRG Associates (2005). 0 Assessment of Undiscovered Oil and Gas in the Wind River Basin Province, Wyoming

A.

40-70 ft.

development of Park City islands Reservoirs: algal boundstones and cross-bedded grainstones 1.5 - 2 miles EXPLANATION B. Lower-intertidal Cross-bedded fenestral boundstones oolite grainstones

Upper-intertidal to supratidal fenestral Salina anhydrites. boundstones

Cherts Lagoonal siltstones

Algal mudstones Restricted-subtidal rocks

0 1 N from Coalson and Inden (1990) mile

Figure 16. Depositional environment of hypothesized reservoirs for undiscovered oil and gas in the Wind River Basin Province. A, model for development of Park City boundstone islands interpreted to be the main reservoir at Cottonwood field in the Bighorn Basin (Coalson and Inden, 1990, their fig. 6D). B, satellite photo of Joulters Cay, Great Bahama Bank, a general analog to the Park City islands. Image courtesy of the Image Science & Analysis Laboratory, NASA Johnson Space Center (image number: ISS004-E-13705). Approximate scale provided.

Table 1. Summary of assessment results for the Phosphoria Total Petroleum System in the Wind River Basin Province, Wyoming. [MMBO, million barrels of oil. BCFG, billion cubic feet of gas. MBNGL, thousand barrels of natural gas liquids. Results shown are fully risked estimates. For gas fields, all liquids are included under the NGL (natural gas liquids) category. F95 represents a 95-percent chance of at least the amount tabulated. Other fractiles are defined similarly. Fractiles are additive under the assumption of perfect positive correla- tion. Gray shade indicates not applicable]

Total Petroleum Systems Total undiscovered resources (TPS) Field Oil (MMBO) Gas (BCFG) NGL (MBNGL) and Assessment Units (AU) type Phosphoria TPS

Tensleep-Park City Conventional Oil 4 16 42 18 4 15 44 19 90 360 1,090 440 Oil and Gas AU Gas 0.00 0.00 0.00 0.00 56 244 600 275 1,040 4,710 12,550 5,490 Total Undiscovered 4 16 42 18 60 259 644 294 1,130 5,070 13,640 5,930 Oil and Gas Resources Undiscovered Oil and Gas—Phosphoria Total Petroleum System—Wind River Basin 1

Acknowledgments Burtner, R.L., and Nigrini, Andrew, 1994, Thermochronol- ogy of the Idaho—Wyoming thrust belt during the Sevier Orogeny: A new, calibrated, multiprocess thermal model: We thank the following individuals for contributions American Association of Petroleum Geologists Bulletin, v. to this report: Chris Anderson, U.S. Geological Survey 78, no. 10, p. 1586-1612. contractor, for GIS analysis; Jeannine Honey of the USGS Carr-Crabaugh, Mary, and Dunn, T.L., 1996, Reservoir het- core library for help in locating cores; Wayne Husband, erogeneity as a function of accumulation and preservation U.S. Geological Survey contractor, for layout and graphic dynamics, Tensleep Sandstone, Bighorn and Wind River design; Tim Klett for his work on production plots; Kreig Basins, Wyoming in Longman, M.W., and Sonnenfeld, Lyles, USGS contractor, graphic design of Phosphoria M.D., eds., Paleozoic Systems of the Rocky Mountain paleogeography and general drafting; Dick Keefer for Region: Rocky Mountain Section, SEPM, p. 305-320. numerous discussions on the geology of the basin; Jim Palacas for compilation and discussions of geochemical data; Chris Cheney, T.M., and Sheldon, R.P., 1959, Permian stratigraphy Potter for discussions of structural geology; Chris Schenk and oil potential, Wyoming and Utah, in Williams, N.C., for discussions of petroleum systems, eolian systems in the ed., Guidebook to the Geology of the Wasatch and Uinta field, and for providing photographs in figure 12; Dave Taylor Mountains Transition Area: Intermountain Association of for making 2-D seismic sections available. We gratefully Petroleum Geologists 10th Annual Field Conference, acknowledge GeoMark Research Inc. for permission to p. 90-100. publish plots of their petroleum geochemistry data. Reviews by Steve Condon, Jim Palacas, and Ofori Pearson and editing Chidsey, Jr., T.C., and Eby, D.E., 2004, Heterogeneous shal- by Dick Keefer greatly improved the manuscript. An edit of low—shelf carbonate buildups in the Paradox Basin, Utah geologic names by Doug Nichols is appreciated. Lyn Osburn and Colorado: Targets for increased oil production and edited the final draft. reserves using horizontal drilling techniques: Utah Geologi- cal Survey Semi-Annual Technical Progress Report April 6, 2004-October 5, 2004, Contract No. DE-FC26-00BC15128, 22 p. References Claypool, G. 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Mallory, W.W., 1972, Regional Synthesis of the Pennsylvanian Palacas, J.G., Flores, R.M., Keighin, C.W., and Anders, D.E., System, in Mallory, W.W., ed., Geologic Atlas of the Rocky 1994, Origin of oil in oil-saturated sandstones in the upper Mountain Region: Rocky Mountain Association of Geolo- part of the Fort Union Formation (Paleocene), Castle Gar- gists, p. 111-127. dens and Signor Ridge areas, Wind River Basin, Wyoming, in Flores, R.M., Mehring, K.T., Jones, R.W., and Beck, T.L., Maughan, E.K., 1976, Organic carbon and selected element eds., Organics and the Rockies Field Guide: Wyoming State distribution in the phosphatic shale members of the Permian Geological Survey, Public Information Circular No. 33, p. Phosphoria Formation, eastern Idaho and parts of adjacent 83-97. states: U.S. Geological Survey Open-File Report 76-577, 92 p. Paull, R.K. and Paull, R.A., 1986, Epilogue for the Permian Maughan, E.K., 1984, Geological setting and some geochem- in the western Cordillera—A retrospective view from the istry of petroleum source rocks in the Permian Phosphoria Triassic: University of Wyoming, Contributions to Geology, Formation, in Woodward, Jane, Meissner, F.F., and Clayton, v. 24, p. 243-252. J.L., eds., Hydrocarbon Source Rocks of the Greater Rocky Mountain region: Rocky Mountain Association of Geolo- Paull, R.K. and Paull, R.A., 1987, Lower Triassic rocks within gists, p. 281-294. and adjacent to the thrust belt of Wyoming, Idaho, and Utah, in Miller, W.R., ed., The Thrust Belt Revisited: Wyoming McIver, R.D., 1962, The crude oils of Wyoming—Product of Geological Association 38th Field Conference Guidebook, depositional environment and alteration, in Enyert, R.L., p. 149-161. and Curry, W.H., III, eds., Symposium on Early Cretaceous rocks of Wyoming and adjacent areas: Wyoming Geological Peterson, Fred, 1988, Pennsylvanian to Jurassic eolian trans- Association Guidebook, 17th Annual Field Conference, portation systems in the western United States: Sedimentary p. 248-251. Geology, v. 56, p. 207-260. McKelvey, V.E., Williams, J.S., Sheldon, R.P., Cressman, Peterson, J.A., 1984, Permian stratigraphy, sedimentary facies, E.R., Cheney, T.M., and Swanson, R.W., 1959, The Phos- and petroleum geology, Wyoming and adjacent areas, in phoria, Park City and Shedhorn Formations in the western Goolsby, Jim, and Morton, Doug, eds., The Permian and phosphate field: U.S. Geological Survey Professional Paper Pennsylvanian Geology of Wyoming: Wyoming Geological 313A, 47 p. Association 35th Annual Field Conference Guidebook, p. 25-64. Medrano, M.D., and Piper, D.Z., 1995, Partitioning of minor elements and major-element oxides between rock compo- Picard, M.D., 1993, The early Mesozoic history of Wyoming, nents and calculation of the marine derived fraction of the in Snoke, A.W., Steidtmann, J.R., and Roberts, S.M., eds., minor elements in rocks of the Phosphoria Formation, Idaho Geology of Wyoming: The Geological Survey of Wyoming and Wyoming: U.S. Geological Survey Open-File Report Memoir No. 5, p. 211-248. 95-270, 79 p. Piper, D.Z., and Link, P.K., 2002, An upwelling model for the Molzer, P.C., and Erslev, E.A., 1995, Oblique convergence Phosphoria sea—A Permian, ocean-margin sea in the north- during northeast-southwest Laramide compression along the west United States: American Association of Petroleum east-west Owl Creek and Casper Mountain Arches, central Geologists Bulletin, v. 86, no. 7, p. 1217-1235. Wyoming: American Association of Petroleum Geologists Bulletin, v. 79, no. 9, p. 1377-1394. Roberts, L.N.R., Lewan, M.D., and Finn, T.M., 2004, Tim- ing of oil and gas generation of petroleum systems in the NRG Associates, 2005, [includes data current as of 2003], The southwestern Wyoming province: Mountain Geologist, v. significant oil and gas fields of the United States: Colorado 41, no. 3, p. 87-118. Springs, Colo., NRG Associates, Inc.; database available from NRG Associates, Inc.; P.O. Box 1655, Colorado Sando, W.J., Mackenzie, Gordon, Jr., and Dutro, J.T., Jr., 1975, Springs, CO 80901, U.S.A. Stratigraphy and geologic history of the Amsden Forma- tion (Mississippian and Pennsylvanian) of Wyoming: U.S. Orr, W.L., 1986, Kerogen/asphaltene/sulfur relationships in Geological Survey Professional Paper 848-A, 83 p. sulfur-rich Monterey oils: Organic Geochemistry, v. 10, p. 499–516. Sharkey, H.R., 1946, Geology and oil possibilities of the Sage Creek Dome, Fremont County, Wyoming: U.S. Geologi- cal Survey Oil and Gas Investigations Preliminary Map 53, scale 1:31,680. Sheldon, R.P., 1967, Long-distance migration of oil in Wyo- ming: Mountain Geologist, v. 4, no. 2, p. 53-65.  Assessment of Undiscovered Oil and Gas in the Wind River Basin Province, Wyoming

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Appendix A. Input data for the Tensleep-Park City Conventional Oil and Gas Assessment Unit (AU 50350101). Seventh Approximation Data Form for Conventional Assessment Units (NOGA, version 5, 06-30-01). Complete form including allocations is shown in Klett and Le (Chapter 2, this CD–ROM).

SEVENTH APPROXIMATION DATA FORM FOR CONVENTIONAL ASSESSMENT UNITS (Version 6, 9 April 2003)

IDENTIFICATION INFORMATION Assessment Geologist: M.A. Kirschbaum Date: 9/21/2005 Region: North America Number: 5 Province: Wind River Basin Number: 5035 Total Petroleum System: Phosphoria Number: 503501 Assessment Unit: Tensleep-Park City Conventional Oil and Gas Number: 50350101 Based on Data as of: IHS Energy Group(2005), Wyoming Geological Association (1989) Notes from Assessor: NRG Associates (2005, data current through 2003)

CHARACTERISTICS OF ASSESSMENT UNIT

Oil (<20,000 cfg/bo overall) or Gas (>20,000 cfg/bo overall): Oil

What is the minimum accumulation size? 0.5 mmboe grown (the smallest accumulation that has potential to be added to reserves)

No. of discovered accumulations exceeding minimum size: Oil: 18 Gas: 2 Established (>13 accums.) X Frontier (1-13 accums.) Hypothetical (no accums.)

Median size (grown) of discovered oil accumulations (mmbo): 1st 3rd 14.4 2nd 3rd 61.3 3rd 3rd 3.1 Median size (grown) of discovered gas accumulations (bcfg): 1st 3rd 2nd 3rd 3rd 3rd

Assessment-Unit Probabilities: Attribute Probability of occurrence (0-1.0) 1. CHARGE: Adequate petroleum charge for an undiscovered accum. > minimum size: 1.0 2. ROCKS: Adequate reservoirs, traps, and seals for an undiscovered accum. > minimum size: 1.0 3. TIMING OF GEOLOGIC EVENTS: Favorable timing for an undiscovered accum. > minimum size 1.0

Assessment-Unit GEOLOGIC Probability (Product of 1, 2, and 3): 1.0

UNDISCOVERED ACCUMULATIONS No. of Undiscovered Accumulations: How many undiscovered accums. exist that are > min. size?: (uncertainty of fixed but unknown values)

Oil Accumulations: minimum (>0) 1 mode 5 maximum 15 Gas Accumulations: minimum (>0) 1 mode 7 maximum 40

Sizes of Undiscovered Accumulations: What are the sizes (grown) of the above accums?: (variations in the sizes of undiscovered accumulations)

Oil in Oil Accumulations (mmbo): minimum 0.5 median 1.5 maximum 50 Gas in Gas Accumulations (bcfg): minimum 3 median 10 maximum 300 6 Assessment of Undiscovered Oil and Gas in the Wind River Basin Province, Wyoming

Appendix A. Input data for the Tensleep-Park City Conventional Oil and Gas Assessment Unit (AU 50350101). Seventh Approximation Data Form for Conventional Assessment Units (NOGA, version 5, 06-30-01). Complete form including allocations is shown in Klett and Le (Chapter 2, this CD–ROM).—Continued

Assessment Unit (name, no.) Tensleep-Park City, 50350101

AVERAGE RATIOS FOR UNDISCOVERED ACCUMS., TO ASSESS COPRODUCTS (uncertainty of fixed but unknown values) Oil Accumulations: minimum mode maximum Gas/oil ratio (cfg/bo) 500 1000 1500 NGL/gas ratio (bngl/mmcfg) 12 24 36

Gas Accumulations: minimum mode maximum Liquids/gas ratio (bliq/mmcfg) 10 20 30 Oil/gas ratio (bo/mmcfg)

SELECTED ANCILLARY DATA FOR UNDISCOVERED ACCUMULATIONS (variations in the properties of undiscovered accumulations) Oil Accumulations: minimum mode maximum API gravity (degrees) 20 28 55 Sulfur content of oil (%) 0.1 3 5 Depth (m) of water (if applicable)

minimum F75 mode F25 maximum Drilling Depth (m) 1000 1866 2000 2775 4000

Gas Accumulations: minimum mode maximum Inert gas content (%) 0 0.3 7

CO2 content (%) 0 0.5 4 Hydrogen-sulfide content (%) 0 0.3 5.5 Depth (m) of water (if applicable)

minimum F75 mode F25 maximum Drilling Depth (m) 1000 2414 3000 3586 5000

Undiscovered Oil and Gas—Phosphoria Total Petroleum System—Wind River Basin 7

ALEOZOIC (part) ALEOZOIC P MESOZOIC (part) MESOZOIC TE 1 A . W - A SERIES DDS-69-J NE T . 44 N., R. 95 A CHAPTER 3, PL R T Lithology from bulk density Lithology from bulk density Lithology from bulk density Low sonic zone; incised fill in base of Park City? IP 4600 4500 4800 4900 5000 5100 5200 4700 AL D 15 102 BO 843 BW 0 MCFG T 724 MCFG ensleep Sandstone 28,253 BO 5,200 TD T 1,256,316 BW 4,382 KB Perf. 4,521-4,600 , sec. 23, 49-017-20740 Gebo Unit 76 1/4 DIGI Embar/ King Dome Field Marathon Oil Company Cumulative production (03/05 WOGCC) , NW Restricted 1/4 subtidal facies (1) G Peritidal facies (1) SE (1) Coalson and Inden (1990) Fm Dinwoody . W Depth of perforated zone shown in red. Depth in feet. Abbreviations: GR, Gamma ray; C, conductivity; R, Resistivity; S, Sonic; NP, Neutron porosity; BD, bulk density C Chapter 3 R . 44 N., R. 96 T 2700 2800 2800 2700 3000 3100 2900 IP -0208729 4 10 BO 572 BO 14 0 MCFG 448 BW 0 MCFG 19,887 BW W 3,165 TD GR 5,360 KB Perf. 3,115-3,125 ensleep Sandstone , sec. 19, T 49-017-20559 Geophysical log explanation 1/4 Ogle Husky Oil Company King Dome Field Cumulative production (03/05 WOGCC) , SE 1/4 SW G , barrels of water; WOGCC, W otal depth T yoming Oil and Gas Conservation Commission. , Initial potential P W Map number Field name API number Operator Lease and well number GL, Ground level; KB, Kelly bushing TD, I Abbreviations: BO, barrels of oil; MCFG, thousand cubic feet of gas; B Producing formation Perforation zone, depth in feet Location (section, township, range) . W Dry hole Oil well Injection well BD . 8 N., R. 4 E. T Header explanation IP 14 10 BO 572 BO . 1 N., R.111 0 MCFG 448 BW 0 MCFG 6,000 GL 19,887 BW 3200 T 3300 3000 2900 3100 2,000 TD Federal 1 49-017-00000 Perf. 3,115-3,125 ensleep Sandstone T 13 , sec. 16, 4,975 GL 3,600 TD Wildcat sec. 1, Marathon Oil Company 1/4 Thromburg 1 49-017-21270 Cumulative Production (03/05 WOGCC) Maverick Springs Field , SW Panaia Oil and Gas Inc. G 1/4 NW Bighorn Basin or karst Darwin Ss in Madison? S . 7 N., R. 4 E. T 1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000 12 exaco Inc. 3,693 TD 5,351 KB , sec. 6, T 49-017-05049 1/4 Kelly Ranch area , SE Shoshone-Arapohoe 1-A 1/4 GR SE ? ? R . 7 N., R. 3E. T ribal 1 Lithology from bulk density Lithology from bulk density Lithology from bulk density (end interpretation) T 900 1200 1300 1400 1500 1600 1700 1800 1900 2000 1000 1100 11 , sec.16 2,803 TD 6,237 KB Wildcat 1/4 49-017-20409 uthill and Barbee T , SE Buffalo Robe 1/4 GR NW ? (part) ensleep Sandstone Amsden Formation Park City Formation Madison Limestone T Dinwoody Formation Chugwater Group (part) Chert Carbonate By 2007 Miscellaneous lithologies . 7 N., R. 1E an Lieu T V Sheep Ridge Measured section Keefer and (1966, pl. 3; reproduced in Sando and others, 1975 secs. 10 and 35, ? Generalized depositional environments marker horizon Predominantly marine limestone or dolomite Predominantly eolian sandstone Continental or marginal marine mudrock and sandstone Marine shale ? ? ALEOZOIC AND LOWER MESOZOIC ROCKS IN THE WIND RIVER BASIN SOUTHERN BIGHORN Mark A. Kirschbaum, Paul G. Lillis, and Laura N.R. Roberts . P NP W Volume Title Page Title Volume ithology from Lithology from sonic log Lithology from sonic log Lithology from sonic log L sonic log (end interpretation) . 6 N., R. 1 T 5500 5200 5100 5600 5700 5300 5400 5800 5900 6000 6100 6200 10 , sec. 11 ribal 11-1 6,160 GL 6,320 TD T Wildcat 1/4 49-013-20657 GR , SW 1/4 American Beryllium Oil Corp. NW . ? W . 6 N., R. 2 R T W ° 7 10 n 1600 1200 9 1400 1300 1500 IP 4 BO e Wind River Basin 0 BW MCFG 80 BW 0 MCFG 21,000 BW iver Basi , sec. 26, ovinc 1,700 TD R r 6,762 KB P Perf. 1,353-1,509 1/4 Ranchester Limestone Member Phosphoria Formation Crown Central 49-013-21247 ribal Ohio 7747 8 n Wind GR T W , NE ° Cumulative production (03/05 WOGCC) 108 , 1/4 y 15 line of sectio Maverick Springs Field Horseshoe Shale Member one z ed 13 14 n t 12 up BD r 11 NW dis iver . R W Darwin Sandstone 7 8 W , Colo. Wind 10 ° r 4 6500 6600 6700 6800 6900 7100 7000 9 Indian Reservatio 109 TIGRAPHIC CROSS SECTION SHOWING UPPER Denve w/ thin sections A . 5 N., R. 1 T GR core B052, USGS librar W ° 110 STR 8 , sec. 24, ribal 4-24 7,569 TD N 5,978 KB Wildcat T N 1/4 44° Impel Energy 49-013-20703 43° , NW 1/4 NW . ensleep T W R currently water injection Phosphoria and . 4 N., R. 1 T Lithology from bulk density ithology from ithology from L bulk density L bulk density (end interpretation) 6300 6400 6500 6600 6700 6800 6900 7000 7100 7200 7200 IP 4 (tie well with figure 11) 84 BO 760 BW 10 MCFG ribal C-28 245,313 BO , sec. 32, 5,157,578 BW T 9,350 TD 19,472 MCFG 5,721 KB Perf. 6,722-6,730 ensleep Sandstone T 1/4 49-013-21081 Marathon (Gulf Oil) GR , SW Cumulative production (03/05 WOGCC) 1/4 Steamboat Butte Field SW ? VEY R ighorn Basin. Wells are pro Stratigraphic cross section showing uppermost Paleozoic and lowermost Mesozoic rocks in the Wind River Basin southern B ighorn Basin. Wells . karst zone in Madison or Darwin Sandstone? W BD TMENT OF THE INTERIOR

R A P . 2 N., R. 1 T Lithology from bulk density IP 7 2400 2500 2600 2700 2800 2900 3000 3100 3200 3300 3400 3500 3600 U.S. DE U.S. GEOLOGICAL SU 25 BW 142 BO 0 MCFG 0 MCFG 607,975 BO , sec. 19, 3,670 TD 6,150 KB 11,427,639 BW ribal A PT 70 Perf. 2,863-3,105 ensleep Sandstone T 1/4 T 49-013-07040 SW Winkelman Field , NW Cumulative production (03/05 WOGCC) GR 1/4 Plate 1. to full-size version for printing). jected into a southwest to northeast line of section. (Double click on image link NW esco Operating Inc. (Pan American Petroleum) W