Depositional patterns in point lookout sandstone, northwest San Juan basin, New Mexico
The Point Lookout Formation, which is well exposed along the northwest margin of the San Juan basin in northwestern New Mexico, includes nearshore sediments deposited during a regression of the Late Cretaceous epicontinental sea in earliest Montanan time. Seven regressive events (time-stratigraphic units) are recognized based on subsurface identification of the transgressive boundaries that rise stratigraphically away from the basin and obliquely traverse lithofacies boundaries. Each unit is composed of three depositional phases (progradation, transgression, and aggradation) that occur in regular succession. Discrete distributary and interdistributary areas were maintained in the initial depositional phases throughout the history of the Point Lookout. Each time-stratigraphic sedimentary unit is the product of a progradational-transgressive depositional couplet. During periods of shoreline stability following transgression a channeled estuarine system developed landward of the retrograded shoreline trend. During this tide-dominated aggradational phase, channels migrated over the back-barrier area and produced the relatively coarser sand facies capping the Point Lookout in the study area. After the estuarine system was infilled, coastal plain facies were established in the former backbarrier zone and progradation was renewed. Each time-stratigraphic coastal sand body acts as a discrete reservoir that interfingers landward with impermeable sediments of the coastal plain facies. Given the necessary present-day structural configuration, major stratigraphic rises corresponding to aggradational phases can act as updip migration boundaries to gas derived from the center of a basin.
- Research Organization:
- Univ. of Texas, Austin
- OSTI ID:
- 6374350
- 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
Facies partitioning and reservoir architecture of a transgressive systems tract from outcrop and subsurface data (Companian, San Juan basin, Colorado, and New Mexico)
Coastal record - preservation potential, and distribution of facies along Upper Cretaceous Point Lookout shoreline, northwest New Mexico
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DEPOSITION
FEDERAL REGION VI
GEOLOGIC DEPOSITS
GEOLOGIC FORMATIONS
GEOLOGIC HISTORY
GEOLOGIC STRUCTURES
MINERAL RESOURCES
NATURAL GAS DEPOSITS
NEW MEXICO
NORTH AMERICA
PETROLEUM DEPOSITS
RESERVOIR ROCK
RESOURCES
ROCKS
SANDSTONES
SEDIMENTARY BASINS
SEDIMENTARY ROCKS
USA