Surface thermal maturity map of Uinta, Piceance, and Eagle basins area, Utah and Colorado

Conference · Mon Feb 01 04:00:00 EST 1988 · AAPG Bull.; (United States)

OSTI ID:5879228

Nuccio, V F; Johnson, R C

Knowledge of thermal maturity is essential for basin analysis studies because heat and heat flow play major roles in mineral formation, hydrocarbon generation and destruction, ground-water flow, and petroleum reservoir quality. The authors studied the thermal maturity of several hundred outcrop samples of coal and carbonaceous shale from Pennsylvanian through Quaternary rocks in the area encompassing the Uinta, Piceance, and Eagle basins of Utah and Colorado. All samples were analyzed for mean random vitrinite reflectance (R/sub m/); thus, thermal maturity is defined by R/sub m/ for this study. Their data show that R/sub m/ generally increases with age of the rock, reflecting increasing burial depth and residence time at maximum temperature. Some coals show local anomalously high maturities because of proximity to Tertiary intrusives. Rocks of the same age show a general decrease in maturity from south to north in all three basins, which probably results from a decrease in geothermal gradients from south to north. In the Uinta basin, R/sub m/ values range from about 0.40 to 0.70% around the margins of the basin to 0.45% in the Altamont-Bluebell oil field near the basin center. In the Piceance basin, R/sub m/ values range from about 0.50 to 0.70% around the margins to about 0.25 to 0.35% in the center. The Eagle basin shows the widest range of R/sub m/ values, from 0.30 to 0.50% around the margins to values in the 4.0% range near the center. Some vitrinite anomalies in the study area are best explained by sampling and analytical problems, such as choosing recycled vitrinite grains from organically lean shales or collecting weathered, oxidized samples.

• Research Organization: Geological Survey, Denver, CO (USA)
• OSTI ID: 5879228
• Report Number(s): CONF-880301-
• Conference Information: Journal Name: AAPG Bull.; (United States) Journal Volume: 72:2
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020200* -- Petroleum-- Reserves
Geology
& Exploration
COLORADO
FEDERAL REGION VIII
GEOLOGIC DEPOSITS
GEOLOGIC STRUCTURES
GEOTHERMAL GRADIENTS
MACERALS
MATURATION
MINERAL RESOURCES
NORTH AMERICA
PETROLEUM DEPOSITS
PICEANCE CREEK BASIN
RESERVOIR ROCK
RESOURCES
SEDIMENTARY BASINS
SOURCE ROCKS
TEMPERATURE GRADIENTS
UINTA BASIN
USA
UTAH
VITRINITE