Abstract

The East Livingston Ridge Delaware Field was discovered in January, 1992 with the completion of the Strata Production Cercion Federal #1. Oil production in the field is from the lower Guadalupian (Permian) Brushy Canyon Formation. Cumulative production from 33 wells through February 1995 is 1.08 MMBO and 1.03 BCF.

The Brushy Canyon Formation in the East Livingston Ridge Field consists of clean (no detrital shales) feldspathic (subarkosic) sandstones and siltstones. The grains are subangular to angular and moderately sorted. The sandstones and siltstones have mean grain sizes of 0.10 mm and 0.06 mm respectively. Quartz overgrowths, carbonate cement, extensive dissolution of feldspars, and emplacement of authigenic clays have altered the original depositional fabric. Authigenic clays present are fibrous illite and expandable mixed layer smectite/illite.

The Brushy Canyon reservoirs of the East Livingston Ridge Field are combination stratigraphic-structural traps. A depositional model for these reservoirs is a sand-rich submarine fan/channel complex. The Brushy Canyon is subdivided into an upper and lower package. This subdivision is based upon a different depositional environment interpreted for each package. The sandstones of the upper Brushy Canyon are interpreted to be massive channel, overbank, and levee facies generally associated with the inner and middle fan. The distal fringe sands of the basal Brushy Canyon are interpreted to be outer fan and basin plain.

The density log best reflects the actual porosity (with respect to core porosity) in the Brushy Canyon of the East Livingston Ridge Field. Water saturations calculated using the Humble relationship are relatively accurate. Shaly sand analysis is not necessary because of the low volume of clay in the Brushy Canyon. The distinction between non-pay and pay should be based on the allowable or tolerable water cut.