Computer Mapping and Prospect Evaluation of Berea Sandstone and Clinton Sandstone Interval in Northeastern Ohio Using Radian's CPS/PC Mapping Software

Brett A. Urian

Radian's CPS/PC mapping package and a standard IMB AT were used to map and evaluate producing zones in the Berea Sandstone and the Clinton sandstone section. Radian's CPS/PC software has several features in addition to computer mapping that help with prospect evaluation. A "windowing" feature allows any portion of the map to be enlarged for a more detailed view. Radian's Grid Editor allows the user to move and bias the contour lines to fit a specific geologic interpretation. A volumetric option calculates volumetric reserves of irregularly shaped reservoirs based on the mapped shape of the reservoir. In this study, Lotus 1-2-3 was used for data base management.

The Berea study area, located in western Wayne County, Ohio, covers 20 mi². Two hundred and seventy data points were used in the study. The average well density is 13.5 wells per square mile. The Berea field trends north-south and covers approximately 1,300 ac. Maximum sandstone thickness in the field is 210 ft. Using a trend-surface algorithm, the average sandstone thickness outside of the 1,300-ac field was calculated to be 30 ft. Residual thickness maps, derived from the calculated trend surface, outline several additional smaller sand bodies.

The Clinton study area is Wayne Township, Wayne County, Ohio. Three hundred and sixty data points were used on this map, giving an average well density of 5.6 wells per square mile. In this study, the Clinton section is divided into two sands, the first and second Clinton. In Wayne Township, the first Clinton ranges in thickness from 0 to 10 ft and the second Clinton ranges from 0 to 35 ft. Several second Clinton sand bodies, deposited as offshore sand bars, are found in Wayne Township. Trend-surface and residual maps were calculated to help isolate these sand bodies.

AAPG Search and Discovery Article #91031©1988 AAPG Eastern Section, Charleston, West Virginia, 13-16 September 1988.