skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Burial history of Upper Cretaceous and Tertiary rocks interpreted from vitrinite reflectance, northern Green River basin, Wyoming

Abstract

The burial history of Upper Cretaceous and Tertiary rocks in the northern Green River basin is difficult to reconstruct for three reasons: (1) most of these rocks do not crop out, (2) there are few stratigraphic markers in the subsurface, and (3) regional uplift beginning during the Pliocene caused erosion that removed most upper Tertiary rocks. To understand better the burial and thermal history of the basin, published vitrinite reflectance (R/sub o/) data from three wells were compared to TTI (time-temperature index) maturation units calculated from Lopatin reconstructions. For each well, burial reconstructions were made as follows. Maximum depth of burial was first estimated by stratigraphic and structural evidence and by extrapolation to a paleosurface intercept of R/sub o/ = 0.2%. This burial was completed by early Oligocene (35 Ma), after which there was no net deposition. The present geothermal gradient in each well as used because there is no geologic evidence for elevated paleotemperature gradients. Using these reconstructions, calculated TTI units agreed with measured R/sub o/ values when minor adjustments were made to the estimated burial depths. Reconstructed maximum burials were deeper than present by 2500-3000 ft (762-914 m) in the Pacific Creek area, by 4000-4500 ft (1219-1372 m)more » in the Pinedale area, and by 0-1000 ft (0-305 m) in the Merna area. However, at Pinedale geologic evidence can only account for about 3000 ft (914 m) of additional burial. This discrepancy is explained by isoreflectance lines, which parallel the Pinedale anticline and indicate that approximately 2000 ft (610 m) of structural relief occurred after maximum burial. In other parts of the basin, isoreflectance lines also reveal significant structural deformation after maximum burial during early Oligocene to early Pliocene time.« less

Authors:
;
Publication Date:
Research Org.:
Geological Survey, Denver, CO
OSTI Identifier:
5924822
Alternate Identifier(s):
OSTI ID: 5924822
Report Number(s):
CONF-8506201-
Journal ID: CODEN: AAPGB
Resource Type:
Conference
Journal Name:
Am. Assoc. Pet. Geol., Bull.; (United States)
Additional Journal Information:
Journal Volume: 69:5; Conference: AAPG Rocky Mountain Section meeting, Denver, CO, USA, 2 Jun 1985
Country of Publication:
United States
Language:
English
Subject:
02 PETROLEUM; SOURCE ROCKS; MATURATION; WYOMING; CRETACEOUS PERIOD; GEOTHERMAL GRADIENTS; MACERALS; OPTICAL PROPERTIES; PETROLEUM GEOLOGY; SEDIMENTARY BASINS; TERTIARY PERIOD; CENOZOIC ERA; FEDERAL REGION VIII; GEOLOGIC AGES; GEOLOGIC STRUCTURES; GEOLOGY; MESOZOIC ERA; NORTH AMERICA; PHYSICAL PROPERTIES; TEMPERATURE GRADIENTS; USA 020200* -- Petroleum-- Reserves, Geology, & Exploration

Citation Formats

Dickinson, W.W., and Law, B.E. Burial history of Upper Cretaceous and Tertiary rocks interpreted from vitrinite reflectance, northern Green River basin, Wyoming. United States: N. p., 1985. Web.
Dickinson, W.W., & Law, B.E. Burial history of Upper Cretaceous and Tertiary rocks interpreted from vitrinite reflectance, northern Green River basin, Wyoming. United States.
Dickinson, W.W., and Law, B.E. Wed . "Burial history of Upper Cretaceous and Tertiary rocks interpreted from vitrinite reflectance, northern Green River basin, Wyoming". United States.
@article{osti_5924822,
title = {Burial history of Upper Cretaceous and Tertiary rocks interpreted from vitrinite reflectance, northern Green River basin, Wyoming},
author = {Dickinson, W.W. and Law, B.E.},
abstractNote = {The burial history of Upper Cretaceous and Tertiary rocks in the northern Green River basin is difficult to reconstruct for three reasons: (1) most of these rocks do not crop out, (2) there are few stratigraphic markers in the subsurface, and (3) regional uplift beginning during the Pliocene caused erosion that removed most upper Tertiary rocks. To understand better the burial and thermal history of the basin, published vitrinite reflectance (R/sub o/) data from three wells were compared to TTI (time-temperature index) maturation units calculated from Lopatin reconstructions. For each well, burial reconstructions were made as follows. Maximum depth of burial was first estimated by stratigraphic and structural evidence and by extrapolation to a paleosurface intercept of R/sub o/ = 0.2%. This burial was completed by early Oligocene (35 Ma), after which there was no net deposition. The present geothermal gradient in each well as used because there is no geologic evidence for elevated paleotemperature gradients. Using these reconstructions, calculated TTI units agreed with measured R/sub o/ values when minor adjustments were made to the estimated burial depths. Reconstructed maximum burials were deeper than present by 2500-3000 ft (762-914 m) in the Pacific Creek area, by 4000-4500 ft (1219-1372 m) in the Pinedale area, and by 0-1000 ft (0-305 m) in the Merna area. However, at Pinedale geologic evidence can only account for about 3000 ft (914 m) of additional burial. This discrepancy is explained by isoreflectance lines, which parallel the Pinedale anticline and indicate that approximately 2000 ft (610 m) of structural relief occurred after maximum burial. In other parts of the basin, isoreflectance lines also reveal significant structural deformation after maximum burial during early Oligocene to early Pliocene time.},
doi = {},
journal = {Am. Assoc. Pet. Geol., Bull.; (United States)},
number = ,
volume = 69:5,
place = {United States},
year = {1985},
month = {5}
}

Conference:
Other availability
Please see Document Availability for additional information on obtaining the full-text document. Library patrons may search WorldCat to identify libraries that hold this conference proceeding.

Save / Share: