Abstract

North Glo Field was discovered in early 1985 and is located in Sec. 2, T50N, R69W, Campbell County, Wyoming. The prospect was developed by detailed subsurface mapping using seismic to "high-grade" the geological concept. This integration of the stratigraphic-seismic method with exploration geology resulted in the discovery of a complex Minnelusa oil pool. The field contains three pay zones; the Cretaceous Muddy and the Permian Minnelusa upper and lower B sands. The Minnelusa Formation is unitized for a polymer augmented waterflood, while the Muddy Formation is shut in.

The Minnelusa lower B sandstone was deposited on the western flank of a paleotopographic feature formed by deposition of thick C sand and Camp Creek sand units. The lower B sandstone consists of two distinct pods of thick eolian dunes separated by an east-west saddle of lower dune sand facies. The paleotopographic low created by this saddle allowed for deposition and preservation of an upper B sand. The upper B sand is overlain by a thin Opeche Shale, typical of areas with upper B and A sandstone development.

The field has an average net pay of 16 ft and covers an area of approximately 300 acres. Average porosities are 16% with permeabilities varying significantly both laterally and vertically throughout the field. Total recoverable reserves with the implementation of secondary recovery should exceed 1.3 MMBO. This would represent a recovery of approximately 29% of the original oil in place.