U.S. Department of the Interior

U.S. Geological Survey

Fact Sheet 2004–3022

March 2004

National Assessment of Oil and Gas Fact Sheet

Assessment of Undiscovered Oil and Gas Resources of the 

Bend Arch-Fort Worth Basin Province of North-Central Texas 

and Southwestern Oklahoma, 2003

Printed on recycled paper

Introduction

The U.S. Geological Survey (USGS) 

recently completed an assessment of the 

undiscovered oil and gas potential of the 

Bend Arch-Fort Worth Basin Province, 

north-central Texas and southwestern 

Oklahoma (fig. 1). The assessment is 

based on geologic elements of each Total 

Petroleum System (TPS) defined in the 

province, including characterization of 

hydrocarbon source rocks (source-rock 

maturation, hydrocarbon generation, and 

migration), reservoir rocks (sequence 

stratigraphy and petrophysical properties), and hydrocarbon traps (trap formation and timing). By using these criteria, 

the USGS defined 4 TPSs and 11 Assessment Units (AUs) within them and quantitatively estimated the undiscovered oil 

and gas resources within 8 of the 11 AUs, 

which represented 3 of the 4 TPSs 

(table 1). The TPSs cover a geographic 

area that includes the bounding structural 

elements of the Bend arch and Fort Worth 

Basin: Ouachita thrust front, the Hardeman Basin, Wichita uplift, Llano uplift, 

Muenster and Red River arches, Broken 

Bone graben, and easternmost part of 

the Eastern shelf of the Permian Basin 

(fig. 1).

Resource Summary

The USGS assessment of undiscovered conventional oil and gas and undiscovered continuous (unconventional) gas 

within the Bend Arch-Fort Worth Basin 

Province resulted in estimated means of 

26.7 trillion cubic feet of gas (TCFG), 

98.5 million barrels of oil (MMBO), and 

a mean of 1.1 billion barrels of natural 

gas liquids (BBNGL) in the three TPSs 

that were assessed (table 1). Nearly all of 

the undiscovered gas resource (98 percent, or 26.2 TCFG) is considered to be 

in continuous accumulations of nonassociated gas trapped in strata of two of 

the three Mississippian-age Barnett Shale 

AUs — the Greater Newark East FracBarrier Continuous Barnett Shale Gas 

AU and the Extended Continuous Barnett 

Shale Gas AU — of the Barnett-Paleozoic TPS. The third AU within this TPS, 

the Hypothetical Basin-Arch Barnett 

Shale Oil AU, was not quantitatively 

assessed because of a lack of data.

The potentially giant continuous 

shale-gas resource (26.2 TCF) within the 

two AUs of the Barnett-Paleozoic TPS 

Using a geology-based assessment methodology, the U.S. 

Geological Survey estimated a mean 

of 26.7 trillion cubic feet (TCF) of 

undiscovered natural gas, a mean of 

98.5 million barrels of undiscovered 

oil, and a mean of 1.1 billion barrels 

of undiscovered natural gas liquids 

in the Bend Arch-Fort Worth Basin 

Province. More than 98 percent, or 

26.2 TCF, of the undiscovered natural 

gas resource is continuous gas in 

Mississippian-age Barnett Shale.

Figure 1. Bend Arch-Fort Worth Basin Province within the boundary outlined in red and primary 

structural elements of north-central Texas and the southwestern corner of Oklahoma.

Austin

Dallas

Houston

Fort

Worth

Ouachita Thrust Front

Bend

Arch

Red River Arch

Muenster Arch

35

35

10

30

20

20

10

102°W 100°W 98°W 96°W

34°N

32°N

30°N

50 Miles

OKLAHOMA

TEXAS

MEXICO

N

Fort Worth

Basin

Permian

Basin

Province

Broken Bone Graben

Eastern

Shelf

Llano

Uplift

Hardeman Basin

Wichita Uplift
had not been previously assessed and is 

included as an addition to reserves by the 

USGS (table 1). The remaining 467 billion cubic feet of gas (BCFG) of the 

estimated undiscovered gas resource in 

the Province is in conventional nonassociated gas accumulations (358.6 BCFG) 

and associated/dissolved gas in conventional oil accumulations (108.4 BCFG). 

The Barnett-Paleozoic TPS is estimated 

to contain a mean of 409.2 BCFG of 

conventional gas, or about 88 percent of 

all undiscovered conventional gas, and 

about 64.6 MMB of conventional oil, or 

about 65 percent of all undiscovered oil 

(table 1) in the Bend Arch-Fort Worth 

Basin Province. 

Two smaller TPSs, the Barnett-Hardeman Basin TPS and the Pennsylvanian 

Bend-Broken Bone Graben TPS, are 

estimated to contain a total mean of about 

12 percent (57.7 BCFG) of undiscovered 

conventional gas, and about 35 percent 

(33.9 MMBO) of the undiscovered 

conventional oil (table 1) in the Province. Because of the lack of data, neither 

the Hypothetical Continuous Fractured 

Barnett Shale Oil AU of the BarnettHardeman Basin TPS, nor the Hypothetical Pennsylvanian-Lower Permian 

Coal-Bed Gas AU of the PennsylvanianLower Permian Coal-Bed Gas TPS, was 

quantitatively assessed (table 1).

For Additional Information

Supporting geologic studies of Total 

Petroleum Systems and Assessment 

Units, and reports on the methodology 

used in the Bend Arch-Fort Worth Basin 

Province assessment are in progress. 

Assessment results are available at the 

USGS Central Energy Team website:

http://energy.cr.usgs.gov/oilgas/noga/

Bend Arch-Fort Worth Basin Province Assessment Team:

Richard M. Pollastro (Task Leader, 

pollastro@usgs.gov), Ronald J. Hill, 

Thomas A. Ahlbrandt, Ronald R. Charpentier, Troy A. Cook, Timothy R. Klett, 

Mitchell E. Henry, and Christopher J. 

Schenk.

Barnett-Paleozoic TPS

Barnett-Paleozoic TPS

Pennsylvanian Bend-Broken Bone Graben TPS

Pennsylvanian-Lower Permian Coal-Bed Gas TPS

Barnett-Hardeman Basin TPS

Barnett-Hardeman Basin TPS

Total Petroleum Systems (TPS)

 and Assessment Units (AU) 

Mississippian Chappel Waulsortian Mounds AU

 Fluvial Sandstone-Carbonate Bank AU

Pennsylvanian/Permian Fluvial-Deltaic Sandstone

and Conglomerate AU

Paleozoic Shelf and Bank Carbonates AU

Paleozoic Clastics and Carbonates AU

Mississippian Chappel Pinnacle Reefs AU

Hypothetical Pennsylvanian-Lower Permian Coal-Bed Gas AU

Greater Newark East Frac-Barrier Continuous Barnett Shale Gas AU

Extended Continuous Barnett Shale Gas AU

Hypothetical Continuous Fractured Barnett Shale Oil AU

TOTAL UNDISCOVERED OIL AND GAS RESOURCES

Total Continuous Resources

Hypothetical Basin-Arch Barnett Shale Oil AU

Total Conventional Resources

Field

Type

Oil

Gas

Oil

Gas

Oil

Gas

Oil

Oil

Oil

Gas

Gas

Gas

Oil

Oil

CBG

Conventional Oil and Gas Resources

Continuous Oil and

Gas Resources

Total undiscovered resources Oil (MMBO)

F95 F50 F5 Mean F95 F50 F5 Mean F95 F50 F5 Mean

7.69 19.85 38.90 21.21 11.30 30.96 66.52 33.92 0.63 1.81 4.22 2.03

46.10 116.83 219.03 123.15 1.70 4.53 9.42 4.92

2.52 5.39 9.89 5.70 2.52 5.83 11.52 6.27 0.11 0.28 0.61 0.31

17.35 44.02 90.63 47.81 0.95 2.57 5.79 2.87

11.58 35.76 69.80 37.66 16.23 51.87 111.71 56.44 1.06 3.53 8.26 3.95

42.39 134.76 262.21 141.59 1.98 6.55 14.04 7.08

7.54 21.08 39.88 22.17 2.19 6.25 12.35 6.65 0.24 0.68 1.39 0.73

1.63 7.01 17.13 7.89 0.26 1.11 2.77 1.26 0.03 0.12 0.31 0.14

1.37 3.42 7.73 3.83 1.20 3.34 8.10 3.83 0.05 0.13 0.33 0.15

15.02 42.23 89.50 46.00 0.53 1.51 3.30 1.66

32.33 92.51 183.33

 98.46 154.56 437.20 874.34 466.92 7.28 21.71 47.67 23.84

13,410.69 14,638.36 15,978.42 14,659.13 406.84 573.70 809.00 586.37

8,305.14 11,361.66 15,543.04 11,569.73 282.01 445.28 703.09 462.79

21,715.83 26,000.02 31,521.46 26,228.86 688.85 1,018.98 1,512.09 1,049.16

32.33 92.51 183.33 98.46 21,870.39 26,437.22 32,395.80 26,695.78 696.13 1,040.69 1,559.76 1,074.00

Not quantitatively assessed

Not quantitatively assessed

Not quantitatively assessed

Gas (BCFG) NGL (MMBNGL)

[MMBO, million barrels of oil. BCFG, billion cubic feet of gas. MMBNGL, million 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 denotes a 95 percent chance of at least the amount tabulated. Other fractiles are defined similarly. 

Fractiles are additive under the assumption of perfect positive correlation. TPS is Total Petroleum System. AU is Assessment Unit. CBG is coalbed gas. Gray shading 

indicates not applicable] 

Table 1. Bend Arch-Fort Worth Basin Province Assessment Results.