A Review of the U.S. Geological Survey 2002 Geologic Assessment of Resources in the Uinta Basin
Kirschbaum, Mark A., Troy Cook, Russell F. Dubiel, Thomas
M. Finn, Paul G. Lillis, Edward A. Johnson, Ronald C.
Johnson, Phillip H. Nelson, Laura N.R. Roberts, and Stephen B.
U.S. Geological Survey, Denver, CO
The U.S. Geological Survey (USGS) completed an assessment
of the undiscovered oil and gas potential of the Uinta Basin in 2002
as required by the Energy Policy and Conservation Act Amendment
of 2000. The assessment was derived from geologically based
hypotheses concerning the quantities of oil and gas that have the
potential to be added to proved reserves in the U.S. The USGS
defined hydrocarbon source rocks, reservoir rocks, and hydrocarbon
traps and seals for five Total Petroleum Systems that included
seventeen conventional and continuous (unconventional) oil and gas
assessment units within the Uinta Basin.
The greatest potential for additional gas was estimated to be within continuous accumulations sourced from marine shale of the Mancos Shale and from coal of the Mesaverde Group. These source rocks are thermally mature, with vitrinite reflectance values exceeding 0.75% Ro in much of the Uinta Basin. Reservoirs are mainly low-permeability Cretaceous and Tertiary fluvial and shoreface sandstones.
Drilling completions in the five years since the assessment include about 1,650 oil and gas wells producing approximately 12 million barrels of oil and 0.4 trillion cubic feet of gas. A high proportion of new gas wells are from the continuous accumulation at Natural Buttes field, an increase predicted in the 2002 assessment.
AAPG Search and Discovery Article #90071 © 2007 AAPG Rocky Mountain Meeting, Snowbird, Utah