Sedimentology of the Mesaverde Formation at Rifle Gap, Colorado and implications for gas-bearing intervals in the subsurface
The exposures of the Mesaverde Formation at Rifle Gap, Colorado, are of a regressive series of marine to fluvial deposits about 1650 m (5000 ft) thick. Grading up out of the marine Mancos Shale, the blanket shoreline sandstones of the Corcoran, Cozzette, and Rollins Sandstones record substages of the regression as delta lobes were activated and abandoned in northwestern Colorado during Late Cretaceous time. The overlying coals, sandstones, and carbonaceous mudstones were deposited on the paludal lower delta plain behind the shoreline. Meandering fluvial systems prograded over the paludal deposits. These systems deposited point-bar sandstones and overbank mudstones and siltstones in composite meander-belt trends, some of which are now gas-bearing, low-permeability reservoirs. Reorientation of the paleogeography during the Laramide orogeny (contemporaneous with fluvial deposition) probably changed the orientation of the meander belt trends. The uppermost sandstones at Rifle Gap, including the Ohio Creek conglomerate, are interpreted as shoreline deposits of a transgression that has been previously unrecognized in the area. Most of the record of this transgression has been destroyed by pre-Eocene erosion. The outcrops at Rifle Gap provide a basis for interpreting subsurface deposis in the Department of Energy's Western Gas Sands Project Multi-Well Experiment, 12 miles away.
- Research Organization:
- Sandia National Labs., Albuquerque, NM (USA)
- DOE Contract Number:
- AC04-76DP00789
- OSTI ID:
- 5313562
- Report Number(s):
- SAND-82-0604; ON: DE82013396
- Country of Publication:
- United States
- Language:
- English
Similar Records
Reservoir sedimentology of Mesaverde rocks at the Multiwell Experiment site and east central Piceance Creek Basin
Mineralogy and petrology aspects of Mesaverde Formation at Rifle Gap, Colorado, specific to the sedimentology and gas-bearing intervals in the subsurface
Related Subjects
020200* -- Petroleum-- Reserves
Geology
& Exploration
58 GEOSCIENCES
580100 -- Geology & Hydrology-- (-1989)
COLORADO
FEDERAL REGION VIII
GEOLOGIC DEPOSITS
GEOLOGIC FORMATIONS
GEOLOGIC STRUCTURES
GEOLOGY
MINERAL RESOURCES
NATURAL GAS DEPOSITS
NORTH AMERICA
PICEANCE CREEK BASIN
RESOURCES
ROCKS
SANDSTONES
SEDIMENTARY BASINS
SEDIMENTARY ROCKS
SEDIMENTS
USA