Cretaceous system stratigraphy and shallow gas resources on the Fort Peck reservation, northeastern Montana

Conference · Sat Jun 01 00:00:00 EDT 1991 · AAPG Bulletin (American Association of Petroleum Geologists); (United States)

OSTI ID:5788597

Monson, L M; Lund, D F ^[1]

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1. Fort Peck Tribes, Poplar, MT (United States)

Five shallow gas-bearing Cretaceous intervals have been identified on the Fort Peck Reservation of northeastern Montana. They include the Lower Judith River Sandstone and shaly sandstone intervals in the Gammon, Niobrara, Greenhorn, and Mowry Formations, Stratigraphic correlations have been carried from southwestern Saskatchewan through the Bowdoin gas field to the reservation. Sparse yet widely distributed gas shows confirm this relatively untested resource. Each of these gas-bearing intervals belongs to a recognized stratigraphic cycle characterized by thick shales overlain by progradational shaly sandstones and siltstones. The bottom cycle (Skull Creek to Mowry) contains considerable nonmarine deposits, especially within the Muddy Sandstone interval, which is thickly developed in the eastern part of the reservation as a large valley-fill network. Some individual sandstone units are not continuous across the reservation. These, and those that correlate, appear to be related to paleotectonic features defined by northwest-trending lineament zones, and by lineament zone intersections. Northeast-trending paleotectonic elements exert secondary influence on stratigraphic isopachs. Circular tectonic elements, which carry through to basement, also have anomalous stratigraphic expression. Conventional drilling has not been conducive to properly testing the Cretaceous gas potential on the reservation, but empirical well-log analysis suggests that gas can be identified by various crossover techniques. The Judith River Formation did produce gas for field use at East Poplar.

• OSTI ID: 5788597
• Report Number(s): CONF-9107109-; CODEN: AABUD
• Journal Information: AAPG Bulletin (American Association of Petroleum Geologists); (United States), Vol. 75:6; Conference: American Association of Petroleum Geologists (AAPG) Rocky Mountain Section meeting, Billings, MT (United States), 28-31 Jul 1991; ISSN 0149-1423
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
MONTANA
PETROLEUM DEPOSITS
FRACTURED RESERVOIRS
PETROLEUM GEOLOGY
GEOLOGIC FORMATIONS
GEOLOGIC FRACTURES
GEOPRESSURED SYSTEMS
MATURATION
POROSITY
RESERVOIR ROCK
RESISTIVITY LOGGING
STRATIGRAPHY
DEVELOPED COUNTRIES
ELECTRIC LOGGING
FEDERAL REGION VIII
GEOLOGIC DEPOSITS
GEOLOGIC STRUCTURES
GEOLOGY
MINERAL RESOURCES
NORTH AMERICA
RESOURCES
USA
WELL LOGGING
020200* - Petroleum- Reserves
Geology
& Exploration