Brushy Canyon Sandstones Study

The Brushy Canyon sandstones are commonly difficult to petrophysically evaluate in terms of differentiating pay from non-pay zones using standard log evaluation techniques. The sandstones often exhibit low resistivity and low contrast pay and have high calculated water saturations. In addition, the sandstones generally have low permeabilities and are sensitive to formation damage. As a result, formation evaluation is a major problem for operators in the trend. Based upon interest expressed by operators in solving the aforementioned reservoir evaluation problems, Core Laboratories has conducted a geological and petrophysical study for improved formation evaluation of Brushy Canyon sandstones.

Using conventional and rotary sidewall cores appropriate rock types where chosen in which advanced rock property data were measured and integrated with log and well test information from each well in order to establish sets of pay and non-pay criteria for the represented rock types. Where available, conventional cores approximately sixty (60) feet in length from each of the fields represented in the study, were photographed in color and sedimentologically analyzed to determine depositional facies. Core description panels were provided that directly correlate core description, depositional facies and core analysis data to open-hole logs. These provide reference type-sections of the reservoirs for the member companies.

The establishment of this database in the area will allow for impr

• Limiting bypassing of productive intervals
• Minimize the unnecessary testing of wet zones
• Differentiate skin-damaged pay zones from non-pay zones
• Provide more accurate reserve calculations
• Twenty six (26) wells
• Conventional and rotary sidewall cores
• Lea and Eddy Counties, New Mexico