Stages of Eocene Lake Uinta, Piceance Creek basin, Colorado

Conference · Tue Mar 01 04:00:00 EST 1983 · Am. Assoc. Pet. Geol., Bull.; (United States)

OSTI ID:6411849

Johnson, R C

Recent stratigraphic studies have greatly improved our knowledge of the relation between the facies of the Green River Formation in the Piceance Creek basin, thus allowing for a more precise interpretation of the development of Eocene Lake Uinta through time. In general, the evolution of Lake Uinta can be divided into six main stages. During the first stage, which is represented by almost half of the preserved Green River section in the central part of the Piceance Creek basin, there were two lakes, one located in the Uinta basin and one in the Piceance Creek basin. The second stage begins with the Long Point transgression in which the lake in the Pieceance Creek basin transgressed across the Douglas Creek arch and connected with the lake in the Uinta basin. Low-grade, clay-rich oil shale is the dominant lithology from this stage, with the exception of some nearshore areas where shallow shelves began to form. The third stage began with an abrupt increase in the kerogen content of the offshore oil shales. The water level appears to have been much more stable during the fourth stage. At the beginning of the fifth stage, water level gradually rose, bringing intermitted oil-shale deposition over about the outer half of the marginal shelves. The final stage of Lake Uinta in the Piceance Creek basin begins with a major transgression, represented approximately by the base of the Mahogany Ledge, a rich oil-shale sequence. The stratigraphic model presented here demonstrates that Lake Uinta evolved with time, and that each succeeding stage represented an accumulation of characteristics acquired during the preceding stages.

• Research Organization: Geological Survey, Denver, CO
• OSTI ID: 6411849
• Report Number(s): CONF-8304200-
• Conference Information: Journal Name: Am. Assoc. Pet. Geol., Bull.; (United States) Journal Volume: 67:3
• Country of Publication: United States
• Language: English

Related Subjects

04 OIL SHALES AND TAR SANDS
040200* -- Oil Shales & Tar Sands-- Reserves
Geology
& Exploration
CENOZOIC ERA
COLORADO
DEPOSITION
FEDERAL REGION VIII
GEOLOGIC AGES
GEOLOGIC DEPOSITS
GEOLOGIC HISTORY
GEOLOGIC STRUCTURES
GEOLOGY
MINERAL RESOURCES
NORTH AMERICA
OIL SHALE DEPOSITS
RESOURCES
SEDIMENTARY BASINS
SOURCE ROCKS
STRATIGRAPHY
TERTIARY PERIOD
USA