Evaluation of reservoirs displaying low permeability in the Caruaçu layers

Abstract

Sandstones in the Caruaçu layers of the Salgado and Fazenda Boa Esperança fiefds, located in the central area of the Recôncavo Basin, state of Bahia, Brazil, generally display thicknesses of over 100 meters. Drill stem testing in open and cased holes, prior to stimulation, has shown verv low productivitv, indicative of reservoirs of low permeabilitv. Nevertheless, these sandstones prove to be good oil producers when properlv stimulated. This paper stresses the importance of integrating geological data obtained during drilling with electrical log data and the results of drill stem testing, both to subsidize decision-making and to guide completion programs.