San Juan sag: A newly discovered basin beneath San Juan volcanic field of south-central Colorado

Conference · Fri Sep 01 00:00:00 EDT 1989 · AAPG Bulletin (American Association of Petroleum Geologists); (USA)

OSTI ID:5499120

Gries, R R

The San Juan sag is a Laramide foreland basin formerly adjacent to and west of the Laramide northern Sangre de Cristo/San Luis highland. Wrench faulting (Eocene ) and rifting (Oligocene and Miocene) split this bounding uplift and formed the San Luis basin adjacent to and east of the sag. Volcanism concealed the San Juan sag with over 10,000 ft of intermediate volcanic deposits, and its presence remained in doubt until oil in the volcanic rocks encouraged exploration for the underlying sedimentary rocks. Drilling through the volcanic field since 1984 has revealed the presence of Paleocene and Eocene( ) clastic sediments, the Cretaceous Lewis, Mancos, and Dakota formations, and the Jurassic Morrison and Junction Creek formations. Additionally, oil and gas shows abound, and minor production has been established. Exploratory drilling and geophysical acquisitions have helped to define basin geometry, reservoir rocks, source rocks, and maturation and burial history.

• OSTI ID: 5499120
• Report Number(s): CONF-8910195--
• Journal Information: AAPG Bulletin (American Association of Petroleum Geologists); (USA), Journal Name: AAPG Bulletin (American Association of Petroleum Geologists); (USA) Vol. 73:9; ISSN AABUD; ISSN 0149-1423
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020200* -- Petroleum-- Reserves
Geology
& Exploration
CENOZOIC ERA
COLORADO
CRETACEOUS PERIOD
EXPLORATION
FEDERAL REGION VIII
GEOLOGIC AGES
GEOLOGIC DEPOSITS
GEOLOGIC FAULTS
GEOLOGIC FORMATIONS
GEOLOGIC FRACTURES
GEOLOGIC HISTORY
GEOLOGIC STRUCTURES
MATURATION
MESOZOIC ERA
MINERAL RESOURCES
NATURAL GAS DEPOSITS
NORTH AMERICA
PETROLEUM DEPOSITS
RESERVOIR ROCK
RESOURCES
RIFT ZONES
SEDIMENTARY BASINS
SOURCE ROCKS
TERTIARY PERIOD
USA