thumbnail

Integrated core-log petrofacies analysis in the construction of a reservoir geomodel: A case study of a mature Mississippian carbonate reservoir using limited data

American Association of Petroleum Geologists Bulletin

By:
, , , , and
DOI: 10.1306/06030504144

Links

Abstract

Small independent operators produce most of the Mississippian carbonate fields in the United States mid-continent, where a lack of integrated characterization studies precludes maximization of hydrocarbon recovery. This study uses integrative techniques to leverage extant data in an Osagian and Meramecian (Mississippian) cherty carbonate reservoir in Kansas. Available data include petrophysical logs of varying vintages, limited number of cores, and production histories from each well. A consistent set of assumptions were used to extract well-level porosity and initial saturations, from logs of different types and vintages, to build a geomodel. Lacking regularly recorded well shut-in pressures, an iterative technique, based on material balance formulations, was used to estimate average reservoir-pressure decline that matched available drillstem test data and validated log-analysis assumptions. Core plugs representing the principal reservoir petrofacies provide critical inputs for characterization and simulation studies. However, assigning plugs among multiple reservoir petrofacies is difficult in complex (carbonate) reservoirs. In a bottom-up approach, raw capillary pressure (Pc) data were plotted on the Super-Pickett plot, and log- and core-derived saturation-height distributions were reconciled to group plugs by facies, to identify core plugs representative of the principal reservoir facies, and to discriminate facies in the logged interval. Pc data from representative core plugs were used for effective pay evaluation to estimate water cut from completions, in infill and producing wells, and guide-selective perforations for economic exploitation of mature fields. The results from this study were used to drill 22 infill wells. Techniques demonstrated here can be applied in other fields and reservoirs. Copyright ?? 2005. The American Association of Petroleum Geologists. All rights reserved.

Additional Publication Details

Publication type:
Article
Publication Subtype:
Journal Article
Title:
Integrated core-log petrofacies analysis in the construction of a reservoir geomodel: A case study of a mature Mississippian carbonate reservoir using limited data
Series title:
American Association of Petroleum Geologists Bulletin
DOI:
10.1306/06030504144
Volume
89
Issue:
10
Year Published:
2005
Language:
English
Larger Work Type:
Article
Larger Work Subtype:
Journal Article
Larger Work Title:
American Association of Petroleum Geologists Bulletin
First page:
1257
Last page:
1274