Abstract

Shippy field is located on the "wildcat fringe" of the main Minnelusa producing fairway in northeastern Wyoming. Nine dry holes were drilled within a one-half mile radius of the field during a period of twenty-two years before its discovery in late 1985. Its discovery is attributed to the use of subsurface well log data and drill stem test information. A subsequently successful program of borehole monitoring and remedial directional drilling allowed for optimal targeting of development wells within the geologic constraints of the reservoir model and, within government spacing regulations.

Shippy field produces from an eastern lobe of the local Permian upper Minnelusa "B" sandstone interval. The reservoir sandstone is interpreted to have accumulated as an eolian dune sand and is preserved amidst a vertically and horizontally complex association of sandy interdunal carbonates and evaporites, paralic sandstones, and shallow marine carbonates. The local "B" interval geology is characterized by an abrupt eastward facies change and local structural complexity. Hydrocarbon entrapment is primarily attributed to structural closure.

Since its discovery, seven productive development wells and three dry holes have been drilled on 40-acre spacing. More than 650,000 barrels of oil have been produced in two years of production from these seven wells.