Comparative study between density porosity and density magnetic resonance porosity: a case study of Sequoia gas reservoir, Mediterranean offshore gas, Egypt

Abstract

This work deals with a comparative study between density porosity and density magnetic resonance porosity in late Pliocene El Wastani gas reservoir, Sequoia field, West Delta Deep Marine (WDDM). In this study, the available well logging data by collecting, gathering, uploading, analyzing, and interpreting are used. Porosity determination, from the petrophysical parameters, routinely considered the most important process. The determined porosity by the two techniques is compared. Density resulting in density porosity (PHIT-D) showed results more than 23% in gas-bearing reservoir zones and less than 22% in non-gas reservoir zones. The porosity determined from integrating nuclear magnetic resonance (NMR) with conventional density porosity resulting in density magnetic resonance porosity (DMRP) showed results less than 33% in gas-bearing reservoir zones and more than 37% non-bearing gas zones. Comparison between the results of the two techniques in gas-bearing zones, PHIT-D is increasing and DMRP is not affected. DMRP considered the best and most true porosity against gas reservoir. This comparison is valid in any gas-bearing formations by using the proposed technique.