AAPG ANNUAL CONFERENCE AND EXHIBITION
Making the Next Giant Leap in Geosciences
April 10-13, 2011, Houston, Texas, USA
Understanding Production Performance at Pinedale from a Geological Perspective
(1) Shell Western Exploration and Production, Denver, CO.
The giant Pinedale gas field, Wyoming, is a maturing, tight gas sandstone reservoir producing from a 6000 ft gross interval of Upper Cretaceous and Lower Tertiary rocks. Although more than 1200 wells have been drilled and completed, there are still fundamental questions regarding controls on production. Production is mostly from matrix permeability. Log response and petrophysical properties are closely related to geologic facies and cements visible in core and thin section. However, productivity patterns in the field sometimes do not correspond well to the intervals of highly amalgamated, more-permeable sandstone. The lower zone of the reservoir has less sandstone, more mudrock, lower porosity and permeability, but higher pressure, leading to consistently better stage productivity and connectivity. The interaction of reservoir geometry, rock properties, water saturation, pressure and artificial fracture properties is best evaluated via integrated petrophysical-static-dynamic models. This is especially important for the decisions facing Pinedale on the economic merits and resource implications of downspacing to greater well density.