Characterization of the Jet Perforation Crushed Zone by SEM and Image Analysis

Abstract

Summary This paper presents a method to measure porosity and permeability alteration of the crushed zone with scanning electron microscopy (SEM) and image analysis. A new phenomenon, shock metamorphism, was used to evaluate shock-wave penetration. Berea sandstone samples were prepared with a modification of the API recommended practice for test-sample preparation. Samples were perforated with low- and medium-penetration shaped charges. Analysis of the low-charge shot sample indicated an average porosity reduction of 25% and an average permeability reduction of 55% in the crushed zone. The sample shot with the medium-penetration shaped charge showed planar-element shock metamorphism.