Journal of Petroleum Geology, Vol.10, No.3, pp. 267-282, 1987

©Copyright 2000 Scientific Press, Ltd.

STYLOLITIC POROSITY IN CARBONATES: A CRITICAL FACTOR FOR DEEP HYDROCARBON PRODUCTION

Albert V. Carozzi and Donald Von Bergen*

* Department of Geology, 245 Natural History Building, University of Illinois at Urbana-Champaign, 1301 W. Green Street, Urbana, Illinois, 61801-2999, U.S.A.

Abstract

Petrographic and petrophysical studies were completed on cores from Atokan (Pennsylvanian) carbonate gas reservoirs at depths in excess of 4,000 m in the Chapman Deep field, Delaware Basin, Texas. Porosity concentration is in pure carbonate microfacies of Donezella algal mound, upper inner slope, oolitic shoal and lagoon of a platform depositional model, which are characterized by sutured, medium- to high-amplitude stylolites. The porosity is predominantly stylolitic, enlarged and surrounded by halos of oomoldic, biomoldic, cement-moldic and vuggy types. Non-sutured, low-amplitude stylolites, confined to argillaceous carbonate microfacies, have no influence on porosity development.