Laboratory and Digital Petrophysical Multiscale Analysis of Porosity Types in Vaca Muerta Formation in El Mangrullo Field

Abstract

Unconventional shales reservoirs are complex in terms of composition, variable scales of analysis (from centimeter to nanometer) and petrophysical properties. To characterize these reservoirs, detailed analyses are required, including studies of rock samples in a wide range of scales. Extracted from a shale gas well (El Mangrullo Field, southwest of Neuquén Basin), the studied core involves a 123 m thick section within the lower enriched section (informally subdivided into Cocina, Parrilla, Orgánico Inferior y Orgánico Superior intervals) of Vaca Muerta Formation. This study consists in processing, interpreting, and integrating all the information from routine petrophysical laboratory studies (Tight Rock Analysis - TRA), well logs and high-resolution rock analysis (Digital Rock Analysis - DRA) using a customized and tailored workflow that provides quantitative and qualitative results. Permeability, total and effective porosity, organic porosity, and their distribution and another petrophysical properties (like pore size distribution, etc.) are characterized. The integration of the laboratory and DRA results allows the elaboration of a permoporous properties model. This model allowed us to integrate petrophysical model with the production of horizontal wells drilled in different sections of Vaca Muerta Formation.