Geologic model of the Middle-Upper Devonian Snipe Lake BHL A pool paltform-reef complex, western Canada

Conference · Tue May 01 04:00:00 EDT 1990 · AAPG Bulletin (American Association of Petroleum Geologists); (USA)

OSTI ID:6676349

Muir, I D; Springate, G L; Mawdsley, J R ^[1]

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1. Esso Resources Canada Ltd., Calgary, Alberta (Canada)

The Snipe Lake BHL 'A' pool reef is one of a number of large Swan Hills atoll reef complexes of Late Devonian age in central Alberta. This study has developed a model for predicting the distribution of reservoir facies in the Snipe Lake A' pool. The reservoir description is an integral component for tailoring an appropriate depletion plan. Variations in reservoir quality are due primarily to depositional attributes. Reservoir facies include reef flat/shoal margin, reef margin/upper foreslope, middle foreslope, and allochthonous foreslope facies. Parts of the grainy lagoon may also be effective reservoir, although vertical permeability tends to be much reduced compared to other reservoir facies. Reef/shoal margin configuration will also affect reservoir quality and continuity. Muddy margin facies are mainly confined to reentrants and may behave as low-permeability barriers to structurally downdip flank water injectors. A chronostratigraphic framework using cycle correlation in the Snipe Lake platform-reef reservoir helped determine facies-controlled reservoir continuity and distribution of low-permeability facies. The platform (53 m thick) consists of five major cycles (A1-5) arranged in a backstepping stacking pattern. Reservoir facies are confined to the uppermost three platform cycles within the pool unit boundary. The Snipe Lake reef complex initiated on the A5 accretionary platform high and comprises four major cycles (BO-2, C) within the unit. The BO cycle contains in excess of 60% of the Snipe Lake recoverable reserves. This lowermost reef cycle is characterized by progradational margins and expanded reservoir facies, presumably due to a combination of prolonged relative stillstand and subdued shallow bathymetry. Other platform-reef cycles are typified by aggradational margins and narrower reservoir facies belts.

• OSTI ID: 6676349
• Report Number(s): CONF-900605--
• Conference Information: Journal Name: AAPG Bulletin (American Association of Petroleum Geologists); (USA) Journal Volume: 74:5
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020200* -- Petroleum-- Reserves
Geology
& Exploration
58 GEOSCIENCES
580000 -- Geosciences
ALBERTA
CANADA
DEVONIAN PERIOD
GEOLOGIC AGES
GEOLOGIC DEPOSITS
GEOLOGIC MODELS
GEOLOGIC STRUCTURES
MINERAL RESOURCES
NORTH AMERICA
PALEOZOIC ERA
PERMEABILITY
PETROLEUM DEPOSITS
POROSITY
REEFS
RESERVOIR ROCK
RESOURCES