LITHOFACIES CHARACTERIZATION OF OIL PRODUCING INTERVALS IN THE UPPER MISSISSIPPIAN AND CHEROKEE GROUP IN THE OPPLIGER AND HARKNESS OIL FIELDS IN NESS COUNTY, KANSAS

Abstract

The Mississippian System and the Cherokee Group in western Kansas have been productive hydrocarbon reservoirs since their discovery in the 1940s. The heterogeneity, data resolution, and structure of the Mississippian make targeting small hydrocarbon reservoirs more difficult. Studies have described the Mississippian lithofacies: muddy dolomite with chert nodules, muddy dolomite, nodular to bedded chert, chert with clay infill, and bioclastic wackestone/grainstone. This study conducted a detailed facies description of the Upper Mississippian and Cherokee Group and created a facies model of the Oppliger and Harkness oil fields. A suite of 13 well-logs were used for a petrophysical characterization to identify and describe different lithofacies in the oil fields. Several types of models were generated in order to account for limitations. Results show that the Upper Cherokee consists of interbedded, cherty limestone, limestone that is partially dolomitized, and siliceous dolomite. Massive bedded Dolomite and Limestone that contain a low silica dominates the Lower Cherokee. The Upper Mississippian interval between 4495 and 4570 feet MD contains beds of cherty dolomite, cherty limestone, and bedded chert with an average thickness of five feet. The bedded chert is located in the middle of the depth interval and at the Mississippian-Cherokee boundary. A stratigraphic model was constructed for the vertical lithofacies distribution for the Oppliger and Harkness oil fields.

AAPG Datapages/Search and Discovery Article #90221 © 2015 Mid-Continent Section, Tulsa, Oklahoma, October 4-6, 2015