Subsurface Glen Rose reef trend in east Texas and west-central Louisiana
The subsurface Glen Rose reef trend in east Texas and west-central Louisiana (Lower Cretaceous Comanchean) is a regressive carbonate complex deposited on a broad shallow water shelf. The Glen Rose reef trend can be differentiated into two separate reef tracts that prograded seaward over a slowly subsiding shelf. It remains to be seen whether the Glen Rose reefs are actual framework reefs or mounds of transported material. Reef facies include poorly sorted caprinidcoral grainstones, moderately sorted peloid and oncolite packstones and grainstones, and well-sorted, very fine grained skeletal grainstones. Coated grains, abraded skeletal fragments, scoured bedding surfaces, and minor cross-beds are evidence for deposition of the reef facies in a high-energy shoal setting. The reefal buildups grade laterally into low-energy shallow water wackestones and mudstones containing toucasids, orbitolinids, and serpulid burrows. Porosities associated with the reefal buildups appear facies controlled. Caprinid-coral packstones and grainstones exhibit intraparticle, moldic, and vuggy porosities of 10 to 15%. Pinpoint microporosity of 5 to 10% are found within the finegrained skeletal grainstones. Fracture porosity enhances permeability in several facies. Moldic and vuggy porosity types are generally secondary whereas intraparticle porosity may be preserved primary. Coarse equant calcite commonly occludes intraparticle, moldic, vuggy, and fracture porosities. Dolomitization within the reef limestones may have acted to create or preserve porosities. Poor production from the Glen Rose reef trend has been attributed to the lack of structural closure.
- Research Organization:
- Louisiana State Univ., Baton Rouge
- OSTI ID:
- 6375419
- Report Number(s):
- CONF-8304200-
- Journal Information:
- Am. Assoc. Pet. Geol., Bull.; (United States), Journal Name: Am. Assoc. Pet. Geol., Bull.; (United States) Vol. 67:3; ISSN AAPGB
- Country of Publication:
- United States
- Language:
- English
Similar Records
Gas reservoirs in Stuart City trend along lower Cretaceous shelf margin in south Texas
Depositional environments, diagenetic history, and porosity development, vacuum San Andres Field, Lea County, New Mexico
Related Subjects
020200* -- Petroleum-- Reserves
Geology
& Exploration
03 NATURAL GAS
030200 -- Natural Gas-- Reserves
Geology
& Exploration
CRETACEOUS PERIOD
FEDERAL REGION VI
GEOLOGIC AGES
GEOLOGIC DEPOSITS
GEOLOGIC STRUCTURES
LITHOLOGY
LOUISIANA
MESOZOIC ERA
MINERAL RESOURCES
NATURAL GAS DEPOSITS
NORTH AMERICA
PETROLEUM DEPOSITS
POROSITY
REEFS
RESOURCE POTENTIAL
RESOURCES
SEDIMENTATION
TEXAS
USA