New Vitrinite Reflectance Data for the Wind River Basin, 

Wyoming

By Mark J. Pawlewicz and Thomas M. Finn

Open-File Report 2013–1002

U.S. Department of the Interior

U.S. Geological Survey
U.S. Department of the Interior

KEN SALAZAR, Secretary

U.S. Geological Survey

Marcia K. McNutt, Director

U.S. Geological Survey, Reston, Virginia: 2013 

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Suggested citation:

Pawlewicz, M.J., and Finn, T.M., 2013, New vitrinite reflectance data for the Wind River Basin, Wyoming: U.S. 

Geological Survey Open-File Report 2013–1002, 11 p. 

Any use of trade, product, or firm names is for descriptive purposes only and does not imply 

endorsement by the U.S. Government. 

Although this report is in the public domain, permission must be secured from the individual 

copyright owners to reproduce any copyrighted material contained within this report.
iii

Contents

Introduction.................................................................................................................................................................... 1

References Cited........................................................................................................................................................... 2

Figures

Figure 1. Map of the Rocky Mountain region showing Laramide Basins................................................................... 3

Figure 2. Index map of the Wind River Basin............................................................................................................ 4

Figure 3. Stratigraphic chart of Cretaceous and Lower Tertiary rocks in the Wind River Basin ................................ 5

Table

Table 1. Vitrinite reflectance data for the Wind River Basin, Wyoming.................................................................... 6
1

New Vitrinite Reflectance Data for the Wind River Basin, 

Wyoming

By Mark J. Pawlewicz and Thomas M. Finn

Introduction

The Wind River Basin is a large Laramide (Late Cretaceous through Eocene) structural and 

sedimentary basin that encompasses about 7,400 square miles in central Wyoming (fig. 1). The basin is 

bounded by the Washakie Range and Owl Creek and southern Bighorn Mountains on the north, the 

Casper arch on the east and northeast, and the Granite Mountains on the south, and Wind River Range 

on the west (figs. 1 and 2).

Important conventional and unconventional oil and gas resources have been discovered and 

produced from reservoirs ranging in age from Mississippian through Tertiary (Fox and Dolton, 1989; 

De Bruin, 1993; Johnson and others, 1996, 2007). In recent years, advances and success in horizontal 

drilling and multistage fracture stimulation have led to an increase in exploration and completion of 

wells in marine shales in other Rocky Mountain Laramide basins that were traditionally considered 

hydrocarbon source rocks. Important parameters that control hydrocarbon production from these shales 

include: reservoir thickness, amount and type of organic matter, and thermal maturity (Milici, 1993; 

Curtis, 2002). The purpose of this report is to present new vitrinite reflectance data collected mainly 

from Cretaceous marine shales in the Wind River Basin to better characterize their thermal maturity and 

hydrocarbon potential. These new data supplement previously published data by Johnson and others 

(1991), Barker and Crysdale (1993), Katz and Liro (1993), Nuccio and others (1993), Pawlewicz 

(1993), Nuccio and others (1996), and Finn and others (2006).

Ninety-nine samples from Cretaceous and Tertiary strata (fig. 3) were collected from well 

cuttings stored at the U.S. Geological Survey Core Research Center in Lakewood, Colorado. Well 

sample locations are shown on figure 2. All samples were analyzed for vitrinite reflectance to 

determine levels of thermal maturation. Preparation of samples for reflectance analysis required (1) 

crushing the larger pieces into 0.25- to 1-millimeter pieces, (2) casting the pieces with epoxy in pre-cut 

and drilled plugs, and (3) curing the samples overnight. Subsequently, a four-step grinding and 

polishing process was implemented that included sanding with progressively finer sandpaper (60 to 600 

grit) followed by a two-step polishing process (0.3 and 0.05 micron). Vitrinite reflectance 

measurements were determined at 500 X magnification using plane-polarized incident white light and a 

546-nanometer monochromatic filter in immersion oil. For samples containing sufficiently high quality 

vitrinite, at least 25 measurements were recorded. For samples of poorer quality, either due to a poor 

polish or to the presence of mineral or other inorganic material, fewer measurements were recorded. 

Analytical results are given in table 1.
2

References Cited

Barker, C.E., and Crysdale, B.L., 1993, Burial and temperature history of gas generation from coaly 

organic matter in the Late Cretaceous Mesaverde Formation and associated rocks in the deeper 

portions of the Wind River Basin, Wyoming, in Stroock, Betty, and Andrew, Sam, eds., Jubilee 

Anniversary 44th Field Conference: Wyoming Geological Association, Guidebook, p. 235–258. 

Curtis, J.B., 2002, Fractured shale-gas systems: American Association of Petroleum Geologists Bulletin, 

v. 86, no. 11, p. 1,921–1,938.

De Bruin, R.H., 1993, Overview of oil and gas geology of Wyoming, in Snoke, A.W., Steidtmann, J.R., 

and Roberts, S.M., eds., Geology of Wyoming: Geological Survey of Wyoming Memoir No. 5, 

p. 836–873.

Dickinson, W.R., Klute, M.A., Hayes, M.J., Janecke, S.U., Lundin, E.R., McKittrick, M.A., and 

Olivares, M.D., 1988, Paleographic and paleotectonic setting of Laramide sedimentary basins in the 

central Rocky Mountain region: Geological Society of America Bulletin, v. 100, p. 1,023–1,039.

Finn, T.M., Roberts, L.N.R., and Pawlewicz, M.J., 2006, Vitrinite reflectance data for the Wind River 

Basin, central Wyoming: U.S. Geological Survey Open-File Report 2006–1015, 4 p.

Fox, J.E., and Dolton, G.L., 1989, Petroleum geology of the Wind River and Bighorn Basins, Wyoming 

and Montana: U.S. Geological Survey Open-File Report 87–450P, 41 p.

Green, G.N., and Drouillard, P.H., 1994, The digital geologic map of Wyoming in ARC/INFO format: 

U.S. Geological Survey Open-File Report 94–0425, scale 1:500,000.

Johnson, R.C., Finn, T.M., Crovelli, R.A., and Balay, R.H., 1996, An assessment of in-place gas 

resources in low-permeability Upper Cretaceous and Lower Tertiary sandstone reservoirs, Wind River 

Basin, Wyoming: U.S. Geological Survey Open-File Report 96–264, 67 p.

Johnson, R.C., Barker, C.E., Pawlewicz, M.J., Crysdale, B.L., Clark, A.C., and Rice, D.D., 1991, 

Preliminary results of coalbed methane assessment of the Wind River Indian Reservation, Wyoming, 

in Schwochow, S.D., Murray, D.K., and Fahy, M.F., eds., Coalbed methane of western North 

America: Rocky Mountain Association of Geologists, p. 273–284.

Johnson, R.C., Finn, T.M., Kirschbaum, M.A., Roberts, S.B., Roberts, L.N.R., Cook, T., and Taylor, 

D.J., 2007, The Cretaceous-Lower Tertiary Composite Total Petroleum System, Wind River Basin, 

Wyoming, Petroleum Systems and Geologic Assessment of Oil and Gas Resources in the Wind River 

Basin Province, Wyoming: U.S. Geological Survey Digital Data Series DDS–69–J, chap. 4, 96 p., 

CD–ROM.

Katz, B.J., and Liro, L.M., 1993, The Waltman Shale Member, Fort Union Formation, Wind River 

Basin—A Paleocene clastic lacustrine source system, in Keefer, W.R., Metzger, W.J., and Godwin, 

L.H., eds., Oil and gas and other resources of the Wind River Basin: Wyoming Geological 

Association Special Symposium, p. 163–174. 

Milici, R.C., 1993, Autogenic gas (self sourced) from shales—An example from the Appalachian Basin: 

U.S. Geological Professional Paper 1570, p. 253–278.

Nuccio, V.F., Finn, T.M., and Pawlewicz, M.J., 1993, Surface vitrinite reflectance study of the Wind 

River Basin, central Wyoming, in Keefer, W.R., Metzger, W.J., and Godwin, L.H., eds., Oil and gas 

and other resources of the Wind River Basin: Wyoming Geological Association Special Symposium, 

p. 307–317.

Nuccio, V.F., Finn, T.M., and Johnson, R.C., 1996, Thermal maturity data for the assessment of gas 

resources in the Wind River Basin, Wyoming: U.S. Geological Survey Open-File Report 96–064, 57 p.

Pawlewicz, M.J., 1993, Vitrinite reflectance and geothermal gradients in the Wind River Basin, in

Keefer, W.R., Metzger, W.J., and Godwin, L.H., eds., Oil and gas and other resources of the Wind 

River Basin: Wyoming Geological Association Special Symposium, p. 295–306. 
3

Figure 1. Map of the Rocky Mountain region extending from southern Montana to northern New Mexico showing 

locations of Laramide sedimentary and structural basins and related features. Modified from Dickinson and 

others (1988).
4

Figure 2. Map showing general outline of the Wind River Basin, bordering mountain ranges, distribution of major 

rock units, and sample localities. Outcrops from Green and Drouillard (1994). Province boundary from 

Johnson and others (2007). Numbers refer to column 1 (map no.) on table 1.
5

Figure 3. Generalized stratigraphic chart of Upper Jurassic, Cretaceous, and lower Tertiary rocks in the Wind 

River Basin. 
6

Table 1. Vitrinite reflectance data and locations for cuttings samples from wells drilled for oil and gas exploration and production in the Wind River 

Basin, Wyoming. Map no. refers to sample location numbers shown on figure 2.

[API, well number assigned by American Petroleum Institute; Tnsp., township; Rng., range; Sec., section; Lith., lithology; %Ro, vitrinite reflectance 

measurement; n, number of readings per sample; nr, no reading. Depth is in feet.]

Map 

no.

API Tnsp. Rng. Sec. Operator Well Top 

depth

Bottom 

depth

Formation Lith. %Ro n

1 49013202250000 30N 94W 8 Oil & Gas Futures Reserve-Govt. 1 2,000 2,010 Mowry shale 0.94 12

1 49013202250000 30N 94W 8 Oil & Gas Futures Reserve-Govt. 1 2,200 2,210 Mowry shale 0.89 12

1 49013202250000 30N 94W 8 Oil & Gas Futures Reserve-Govt. 1 2,330 2,340 Thermopolis shale 0.99 17

2 49013057600000 33N 90W 4 Superior Oil Govt.-Davis 81-4 2,060 2,070 Frontier shale 0.57 5

2 49013057600000 33N 90W 4 Superior Oil Govt.-Davis 81-4 2,740 2,770 Frontier shale 0.82 11

2 49013057600000 33N 90W 4 Superior Oil Govt.-Davis 81-4 3,000 3,010 Mowry shale 0.61 9

2 49013057600000 33N 90W 4 Superior Oil Govt.-Davis 81-4 3,260 3,280 Mowry shale 0.62 6

2 49013057600000 33N 90W 4 Superior Oil Govt.-Davis 81-4 3,400 3,410 Thermopolis shale 1.30 9

3 49013204640000 33N 93W 26 Oil Resources Govt-Curry 26-12 2,230 2,260 Frontier shale 0.63 15

3 49013204640000 33N 93W 26 Oil Resources Govt-Curry 26-12 2,500 2,510 Mowry shale 0.82 7

3 49013204640000 33N 93W 26 Oil Resources Govt-Curry 26-12 2,650 2,660 Mowry shale 0.81 8

3 49013204640000 33N 93W 26 Oil Resources Govt-Curry 26-12 2,760 2,770 Thermopolis shale 0.69 10

4 49013211920000 33N 98W 30 R. Klabzuba 1-30 Federal 1,770 1,780 Mowry shale 0.99 16

4 49013211920000 33N 98W 30 R. Klabzuba 1-30 Federal 2,000 2,020 Mowry shale 0.70 6

4 49013211920000 33N 98W 30 R. Klabzuba 1-30 Federal 2,200 2,210 Thermopolis shale 0.96 17

4 49013211920000 33N 98W 30 R. Klabzuba 1-30 Federal 2,340 2,350 Cloverly shale 1.24 10
7

Table 1. Vitrinite reflectance data and locations for cuttings samples from wells drilled for oil and gas exploration and production in the Wind River 

Basin, Wyoming. Map no. refers to sample location numbers shown on figure 2.—Continued

[API, well number assigned by American Petroleum Institute; Tnsp., township; Rng., range; Sec., section; Lith., lithology; %Ro, vitrinite reflectance 

measurement; n, number of readings per sample; nr, no reading. Depth is in feet.]

Map 

no.

API Tnsp. Rng. Sec. Operator Well Top 

depth

Bottom 

depth

Formation Lith. %Ro n

5 49025210670000 34N 87W 9 Davis Oil 1 RK Federal 4,680 4,710 Mesaverde coal 0.46 25

5 49025210670000 34N 87W 9 Davis Oil 1 RK Federal 7,310 7,320 Cody shale 0.82 10

5 49025210670000 34N 87W 9 Davis Oil 1 RK Federal 7,660 7,670 Cody shale 0.53 11

5 49025210670000 34N 87W 9 Davis Oil 1 RK Federal 9,530 9,540 Cody shale 0.83 11

5 49025210670000 34N 87W 9 Davis Oil 1 RK Federal 10,310 10,340 Frontier shale 0.62 11

5 49025210670000 34N 87W 9 Davis Oil 1 RK Federal 10,690 10,700 Mowry shale 0.73 13

5 49025210670000 34N 87W 9 Davis Oil 1 RK Federal 10,820 10,830 Thermopolis shale 0.53 7

6 49025058260000 34N 88W 20 M.K.M Exploration 1 Wolters-Fed. 1,560 1,570 Mowry shale 0.64 12

6 49025058260000 34N 88W 20 M.K.M Exploration 1 Wolters-Fed. 1,900 1,920 Mowry shale 0.55 9

6 49025058260000 34N 88W 20 M.K.M Exploration 1 Wolters-Fed. 2,020 2,030 Thermopolis shale 0.70 11

7 49013069220000 35N 92W 31 Sun Oil Company Wolf-Federal 1 1,880 1,900 Fort Union coal 0.68 19

7 49013069220000 35N 92W 31 Sun Oil Company Wolf-Federal 1 3,040 3,060 Meeteetse coal 0.54 11

7 49013069220000 35N 92W 31 Sun Oil Company Wolf-Federal 1 3,790 3,810 Mesaverde coal 0.56 27

7 49013069220000 35N 92W 31 Sun Oil Company Wolf-Federal 1 5,030 5,060 Mesaverde coal 0.54 13

7 49013069220000 35N 92W 31 Sun Oil Company Wolf-Federal 1 8,970 8,980 Cody shale 0.92 17

7 49013069220000 35N 92W 31 Sun Oil Company Wolf-Federal 1 9,700 9,710 Frontier shale 1.08 12

7 49013069220000 35N 92W 31 Sun Oil Company Wolf-Federal 1 9,900 9,910 Mowry shale 0.93 10

7 49013069220000 35N 92W 31 Sun Oil Company Wolf-Federal 1 10,060 10,070 Mowry shale 1.11 9

7 49013069220000 35N 92W 31 Sun Oil Company Wolf-Federal 1 10,190 10,200 Thermopolis shale 1.10 12
8

Table 1. Vitrinite reflectance data and locations for cuttings samples from wells drilled for oil and gas exploration and production in the Wind River 

Basin, Wyoming. Map no. refers to sample location numbers shown on figure 2.—Continued

[API, well number assigned by American Petroleum Institute; Tnsp., township; Rng., range; Sec., section; Lith., lithology; %Ro, vitrinite reflectance 

measurement; n, number of readings per sample; nr, no reading. Depth is in feet.]

Map 

no.

API Tnsp. Rng. Sec. Operator Well Top 

depth

Bottom 

depth

Formation Lith. %Ro n

8 49025217680000 36N 86W 8 Coastal Oil & Gas Bullfrog 3-8-36-86 12,680 12,710 Mesaverde coal 0.57 7

8 49025217680000 36N 86W 8 Coastal Oil & Gas Bullfrog 3-8-36-86 13,640 13,650 Cody shale 1.18 12

8 49025217680000 36N 86W 8 Coastal Oil & Gas Bullfrog 3-8-36-86 15,000 15,010 Cody shale 1.24 9

8 49025217680000 36N 86W 8 Coastal Oil & Gas Bullfrog 3-8-36-86 16,000 16,020 Cody shale 1.54 7

8 49025217680000 36N 86W 8 Coastal Oil & Gas Bullfrog 3-8-36-86 17,140 17,160 Cody shale 1.46 8

8 49025217680000 36N 86W 8 Coastal Oil & Gas Bullfrog 3-8-36-86 18,230 18,250 Frontier shale 1.74 7

8 49025217680000 36N 86W 8 Coastal Oil & Gas Bullfrog 3-8-36-86 19,310 19,320 Frontier shale nr

8 49025217680000 36N 86W 8 Coastal Oil & Gas Bullfrog 3-8-36-86 19,450 19,460 Mowry shale 2.01 9

8 49025217680000 36N 86W 8 Coastal Oil & Gas Bullfrog 3-8-36-86 19,640 19,650 Mowry shale 2.41 10

8 49025217680000 36N 86W 8 Coastal Oil & Gas Bullfrog 3-8-36-86 19,800 19,820 Thermopolis shale 2.19 10

9 49013205650000 36N 94W 25 Pan Canadian Fuller Reservoir II 10,800 10,810 Cody shale 1.33 13

9 49013205650000 36N 94W 25 Pan Canadian Fuller Reservoir II 12,000 12,040 Cody shale 1.23 8

9 49013205650000 36N 94W 25 Pan Canadian Fuller Reservoir II 13,310 13,320 Cody shale 1.52 17

9 49013205650000 36N 94W 25 Pan Canadian Fuller Reservoir II 13,850 13,870 Frontier shale 1.43 13

9 49013205650000 36N 94W 25 Pan Canadian Fuller Reservoir II 14,130 14,140 Frontier shale 1.68 15

9 49013205650000 36N 94W 25 Pan Canadian Fuller Reservoir II 14,350 14,360 Mowry shale 1.44 11

9 49013205650000 36N 94W 25 Pan Canadian Fuller Reservoir II 14,560 14,570 Mowry shale 1.72 12

9 49013205650000 36N 94W 25 Pan Canadian Fuller Reservoir II 14,650 14,670 Thermopolis shale 1.70 17

10 49013204400000 5N 1E 10 Continental Oil Tribal 10-1 7,100 7,110 Cody shale 0.68 11

10 49013204400000 5N 1E 10 Continental Oil Tribal 10-1 8,300 8,310 Mowry shale 0.73 13

10 49013204400000 5N 1E 10 Continental Oil Tribal 10-1 8,500 8,510 Mowry shale 0.72 15

10 49013204400000 5N 1E 10 Continental Oil Tribal 10-1 8,710 8,720 Thermopolis shale 0.78 15
9

Table 1. Vitrinite reflectance data and locations for cuttings samples from wells drilled for oil and gas exploration and production in the Wind River 

Basin, Wyoming. Map no. refers to sample location numbers shown on figure 2.—Continued

[API, well number assigned by American Petroleum Institute; Tnsp., township; Rng., range; Sec., section; Lith., lithology; %Ro, vitrinite reflectance 

measurement; n, number of readings per sample; nr, no reading. Depth is in feet.]

Map 

no.

API Tnsp. Rng. Sec. Operator Well Top 

depth

Bottom 

depth

Formation Lith. %Ro n

11 49013061630000 2N 2W 11 Stanolind Oil & Gas 1 Yamba 870 880 Cody shale 0.89 10

11 49013061630000 2N 2W 11 Stanolind Oil & Gas 1 Yamba 1,790 1,800 Cody shale 0.97 16

11 49013061630000 2N 2W 11 Stanolind Oil & Gas 1 Yamba 3,050 3,080 Frontier shale 1.14 11

11 49013061630000 2N 2W 11 Stanolind Oil & Gas 1 Yamba 3,230 3,240 Mowry shale 0.99 11

11 49013061630000 2N 2W 11 Stanolind Oil & Gas 1 Yamba 3,550 3,560 Mowry shale 0.89 8

11 49013061630000 2N 2W 11 Stanolind Oil & Gas 1 Yamba 3,660 3,730 Thermopolis shale 1.10 14

11 49013061630000 2N 2W 11 Stanolind Oil & Gas 1 Yamba 3,830 3,860 Cloverly shale 1.28 12

12 49013202830000 3N 1W 33 Norris Oil Tribal-McBride 1 3,230 3,260 Frontier shale 0.29 1

12 49013202830000 3N 1W 33 Norris Oil Tribal-McBride 1 3,440 3,470 Mowry shale 0.54 11

12 49013202830000 3N 1W 33 Norris Oil Tribal-McBride 1 3,650 3,670 Mowry shale 0.51 14

12 49013202830000 3N 1W 33 Norris Oil Tribal-McBride 1 3,850 3,870 Thermopolis shale 0.51 11

13 49013213430000 4N 3W 29 Gulf Oil Company Crowheart Butte SW 1-29-3D 2,100 2,130 Cody shale 0.67 12

13 49013213430000 4N 3W 29 Gulf Oil Company Crowheart Butte SW 1-29-3D 3,720 3,750 Mowry shale 0.79 21

13 49013213430000 4N 3W 29 Gulf Oil Company Crowheart Butte SW 1-29-3D 4,110 4,140 Mowry shale 0.99 19

13 49013213430000 4N 3W 29 Gulf Oil Company Crowheart Butte SW 1-29-3D 4,320 4,330 Thermopolis shale 0.94 14

14 49013203030000 4N 4W 35 Stoltz & Company 1-35 Tribal 600 610 Mowry shale 1.10 8

14 49013203030000 4N 4W 35 Stoltz & Company 1-35 Tribal 860 890 Mowry shale 0.94 6

14 49013203030000 4N 4W 35 Stoltz & Company 1-35 Tribal 1,050 1,060 Thermopolis shale 0.89 13

14 49013203030000 4N 4W 35 Stoltz & Company 1-35 Tribal 1,200 1,210 Cloverly shale 1.06 13
10

Table 1. Vitrinite reflectance data and locations for cuttings samples from wells drilled for oil and gas exploration and production in the Wind River 

Basin, Wyoming. Map no. refers to sample location numbers shown on figure 2.—Continued

[API, well number assigned by American Petroleum Institute; Tnsp., township; Rng., range; Sec., section; Lith., lithology; %Ro, vitrinite reflectance 

measurement; n, number of readings per sample; nr, no reading. Depth is in feet.]

Map 

no.

API Tnsp. Rng. Sec. Operator Well Top 

depth

Bottom 

depth

Formation Lith. %Ro n

15 49013065670000 5N 2W 6 Empire State Oil Tribal 1 1,780 1,800 Cody shale 0.84 12

15 49013065670000 5N 2W 6 Empire State Oil Tribal 1 2,800 2,820 Mowry shale 0.66 13

15 49013065670000 5N 2W 6 Empire State Oil Tribal 1 3,400 3,410 Mowry shale 0.68 9

15 49013065670000 5N 2W 6 Empire State Oil Tribal 1 3,650 3,660 Thermopolis shale 0.64 7

16 49013208510000 5N 5W 16 Helmerich & Payne 1-16 Tribal 440 460 Mowry shale 1.01 9

16 49013208510000 5N 5W 16 Helmerich & Payne 1-16 Tribal 750 760 Mowry shale 0.85 10

16 49013208510000 5N 5W 16 Helmerich & Payne 1-16 Tribal 900 910 Thermopolis shale 0.84 12

16 49013208510000 5N 5W 16 Helmerich & Payne 1-16 Tribal 1,100 1,110 Cloverly shale 0.92 6

17 49013067400000 6N 1W 4 British-American Oil Tribal 1 720 770 Frontier coal 0.50 25

17 49013067400000 6N 1W 4 British-American Oil Tribal 1 1,010 1,050 Mowry shale 0.81 20

17 49013067400000 6N 1W 4 British-American Oil Tribal 1 1,320 1,330 Mowry shale 0.95 8

17 49013067400000 6N 1W 4 British-American Oil Tribal 1 1,500 1,530 Thermopolis shale 0.93 5

18 49013206120000 1S 2E 2 Exxon Corporation 1 Shoshone-Arapahoe 534 6,210 6,240 Cody shale 0.47 17

18 49013206120000 1S 2E 2 Exxon Corporation 1 Shoshone-Arapahoe 534 7,600 7,610 Cody shale 0.93 4

18 49013206120000 1S 2E 2 Exxon Corporation 1 Shoshone-Arapahoe 534 8,450 8,460 Frontier shale 0.91 9

18 49013206120000 1S 2E 2 Exxon Corporation 1 Shoshone-Arapahoe 534 8,850 8,860 Mowry shale 0.89 10

18 49013206120000 1S 2E 2 Exxon Corporation 1 Shoshone-Arapahoe 534 9,060 9,070 Thermopolis shale 1.03 12
11

Table 1. Vitrinite reflectance data and locations for cuttings samples from wells drilled for oil and gas exploration and production in the Wind River 

Basin, Wyoming. Map no. refers to sample location numbers shown on figure 2.—Continued

[API, well number assigned by American Petroleum Institute; Tnsp., township; Rng., range; Sec., section; Lith., lithology; %Ro, vitrinite reflectance 

measurement; n, number of readings per sample; nr, no reading. Depth is in feet.]

Map 

no.

API Tnsp. Rng. Sec. Operator Well Top 

depth

Bottom 

depth

Formation Lith. %Ro n

19 49013060040000 1S 5E 1 Continental Oil 1 Tribal 6,880 6,890 Cody shale 0.85 10

19 49013060040000 1S 5E 1 Continental Oil 1 Tribal 8,210 8,220 Cody shale 0.86 16

19 49013060040000 1S 5E 1 Continental Oil 1 Tribal 9,790 9,800 Frontier shale 1.01 19

19 49013060040000 1S 5E 1 Continental Oil 1 Tribal 10,450 10,470 Frontier shale 1.01 15

19 49013060040000 1S 5E 1 Continental Oil 1 Tribal 10,850 10,860 Mowry shale 1.19 13

19 49013060040000 1S 5E 1 Continental Oil 1 Tribal 11,000 11,020 Thermopolis shale 1.17 13