Carbonate mound reservoirs in the paradox formation: An outcrop analogue along the San Juan River, Southeastern Utah

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

OSTI ID:272609

Chidsey, Jr, T C; Morgan, C D ^[1]; Eby, D E ^[2]

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1. Utah Geological Survey, Salt Lake City, UT (United States)
2. Eby Petrography & Consulting, Inc., Littleton, CO (United States); and others

Carbonate mound reservoirs within the Pennsylvanian (Desmoinesian) Paradox Formation are major producers of oil and gas in the Paradox basin of Utah, Colorado, and Arizona. Outcrops of the Paradox Formation along the San Juan River of southeastern Utah provide small-scale analogues of reservoir heterogeneity, flow barriers and baffles, lithofacies, and geometry. These characteristics can be used in reservoir simulation models for secondary/tertiary recovery of oil from small fields in the basin. Exposures of the Paradox Formation Ismay zone in the Wild Horse Canyon area display lateral facies changes from phylloid algal mounds to off-mound detrital wedges or fans bounded at the top by a flooding surface. The phylloid mounds are composed of bafflestone, skeletal grainstone, packstone, and cementstone. Algal plates, brachiopods, bryozoans, and rugose corals are commonly found in the phylloid mounds. The mound wall is composed of rudstone, lumpstone, and cementstone. The detrital fan consists of transported algal material, grainstone, and mudstone with open-marine fossils. Within the mound complex is an inter-mound trough tentatively interpreted to be a tidal channel. The geometry and composition of the rocks in the trough significantly add to the overall heterogeneity of the mound. Reservoir models are being developed for possible water- and carbon-dioxide floods of small Paradox basin fields to determine the most effective secondary/tertiary recovery method. The models will include lithologic fabrics, flooding surfaces, and inter-mound troughs, based on the mound complex exposed at Wild Horse Canyon. This project may also provide reservoir information for simulation models in small Paleozoic carbonate mound fields in other basins worldwide.

• OSTI ID: 272609
• 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
CARBONIFEROUS PERIOD
EXPLORATION
GEOLOGIC MODELS
GEOMETRY
NATURAL GAS
PETROLEUM
PRODUCTION
RESERVOIR ROCK
SEDIMENTARY BASINS
STRATIGRAPHY
UTAH