U.S. Department of the Interior

U.S. Geological Survey

Printed on recycled paper

and a mean of 148 

million barrels of 

natural gas liquids 

in the San Juan 

Basin Province.

Introduction

The U.S. Geological Survey (USGS) recently completed an assessment 

of the undiscovered oil and gas potential of the San Juan Basin Province of 

northwestern New Mexico and southwestern Colorado (fig. 1). The assessment of the San Juan Basin Province is based on the geologic elements of 

each Total Petroleum System defined in the province, including hydrocarbon 

source rocks (source-rock maturation, hydrocarbon generation and migration), reservoir rocks (sequence stratigraphy and petrophysical properties), and 

hydrocarbon traps (trap formation and timing). Using this geologic framework, the USGS defined four Total Petroleum Systems and 14 Assessment 

Units within these Total Petroleum Systems and quantitatively estimated the 

undiscovered oil and gas resources within the 14 Assessment Units (table 1).

Resource Summary

The USGS assessed undiscovere

(unconventional) gas. The USGS est

gas (TCFG), a mean of 19 million ba

million barrels of total natural gas liq

Systems. Nearly all (99.9 percent) of 

ous (table 1). Of the 50.6 TCFG of u

TCFG is estimated to be in the Fruitl

of this 29.2 TCFG (23.5 TCFG) is Fr

Total Petroleum System is estimated 

Mancos-Menefee Total Petroleum Sy

TCFG, of which about 6 percent (0.6

The Mancos-Menefee Total Petr

16.8 MMB of undiscovered convent

of the undiscovered oil (19.1 MMBO

undiscovered conventional oil is esti

reservoirs of the Todilto Total Petrol

Figure 1. San Juan Basin Province of northwestern New Mexico and southwestern Colora

FS-147-02.indd 1 
7.00 17.76 35.92 19.10 59.06 153.24 310.80 165.15 1.

9.14 20.52 9.63 14.80 3,865.41 5,510.68 7,856.23 5,640.25 9.

2.74 9.14 20.52 9.63 14.80 3,081.06 3,937.16 5,031.14 3,981.14 0.

2.74 9.14 20.52 9.63 14.80 17,342.26 19,543.12 22,023.27 19,594.74 0.

2.74 9.14 20.52 9.63 14.80 8,315.22 10,105.95 12,282.31 10,177.24 18.

1,053.32 1,305.62 1,618.35 1,316.79 1,053.32 1,305.62 1,618.35 1,316.79 3.

2.74 9.14 20.52 9.63 14.80 3,980.80 5,062.07 6,437.03 5,116.37 50.

2.74 9.14 20.52 9.63 14.80 3,148.66 3,896.17 4,821.14 3,928.98 10.

228.30 569.08 1,418.55 663.94 0.

41,015.03 49,929.85 61,488.02 50,419.45 91.

7.00 17.76 35.92 19.10 41,074.09 50,083.09 61,798.82 50,584.60 92.

Gas

CBG

CBG

Gas

Gas

Gas

Gas

CBG

Continuous Oil and Gas Resources

Total Continuous

Resources

Total Undiscovered

Oil and Gas Resources

Fruitland TPS

Lewis Shale TPS

Pictured Cliffs Continuous Gas

Fruitland Fairway Coal-Bed Gas

Basin Fruitland Coal-Bed Gas

Lewis Continuous Gas

Mesaverde Central-Basin 

Continuous Gas

Mancos Sandstone Continuous Gas

Dakota-Greenhorn Continuous Gas

Menefee Coal-Bed Gas

Total Conventional

Resources

Mancos-Menefee

Composite TPS

For Further Information

Supporting geologic studies of Total Petroleum Systems and 

Assessment Units, and reports on the methodology used in the San 

Juan Basin Province assessment, are in progress. Assessment results 

are available at the USGS Central Energy Team website:

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

San Juan Basin Province Ass

Jennie L. Ridgley (Task Lead

Condon, Russell F. Dubiel, Rona

Robert A. Crovelli, Timothy R. K

Christopher J. Schenk.

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