Integrated study of Mississippian Lodgepole Waulsortian Mounds, Williston Basin, USA

Journal Article · Sat Jun 01 04:00:00 EDT 1996 · AAPG Bulletin

DOI:https://doi.org/10.1190/1.1826657· OSTI ID:272627

Kupecz, J A; Arestad, J F; Blott, J E ^[1]

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1. Kupecz and Associates, Ltd., Denver, CO (United States)

Waulsortian-type carbonate buildups in the Mississippian Lodgepole Formation, Williston Basin, constitute prolific oil reservoirs. Since the initial discovery in 1993, five fields have been discovered: Dickinson Field (Lodgepole pool); Eland Field; Duck Creek Field, Versippi Field; and Hiline Field. Cumulative production (October, 1995) is 2.32 million barrels of oil and 1.34 BCF gas, with only 69,000 barrels of water. Oil gravity ranges from 41.4 to 45.3 API. Both subsurface cores from these fields as well as outcrop (Bridget Range, Big Snowy and Little Belt Mountains, Montana) are composed of facies representing deposition in mound, reworked mound, distal reworked mound, proximal flank, distal flank, and intermound settings. Porosity values within the mound and reworked mound facies are up to 15%; permeability values (in places fracture-enhanced) are up to tens of Darcies. Geometries of the mounds are variable. Mound thicknesses in the subsurface range from approximately 130-325 feet (40-100 meters); in outcrop thicknesses range from less than 30 ft (9 m) to over 250 ft (76 m). Subsurface areal dimensions range from approximately 0.5 x 1.0 mi (0.8 x 1.6 km) to 3.5 x 5.5 mi (5.6 x 8.8 km). Integration of seismic data with core and well-log models sheds light on the exploration for Lodgepole mounds. Seismic modeling of productive mounds in the Dickinson and Eland fields identifies characteristics useful for exploration, such as local thickening of the Lodgepole to Three Forks interval. These observations are confirmed in reprocessed seismic data across Eland field and on regional seismic data. Importantly, amplitude versus offset modeling identifies problems with directly detecting and identifying porosity within these features with amplitude analyses. In contrast, multicomponent seismic data has great potential for imaging these features and quantifying porous zones within them.

• Sponsoring Organization: USDOE
• OSTI ID: 272627
• Report Number(s): CONF-9607116--
• Journal Information: AAPG Bulletin, Journal Name: AAPG Bulletin Journal Issue: 6 Vol. 80; ISSN 0149-1423; ISSN AABUD2
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
03 NATURAL GAS
CARBONATE ROCKS
COLORADO
GEOMETRY
NATURAL GAS
NATURAL GAS FIELDS
OIL FIELDS
PETROLEUM
PRODUCTION
RESERVOIR ROCK
SEISMIC SURVEYS
STRATIGRAPHY
WILLISTON BASIN