Reservoir Characterization of the Middle/Upper Jurassic Sargelu and Najmah Formations, West Kuwait: Key Workflows and Findings for Future Development of Unconventionals

Abstract

Whole cores provide important and high-quality information about mineralogy, rock fabric and texture, porosity, saturations, geomechanical properties, facies stacking patterns, depositional environment, and fracture networks that often cannot be discerned with much certainty using other subsurface data sets. Here we present results from the detailed digital sedimentologic descriptions of three whole cores in West Kuwait that capture portions of the Middle/Upper Jurassic Najmah Formation, an important source rock and unconventional reservoir. The integration of detailed digital core descriptions with high-resolution XRF scanning of the cores, high-density routine core analysis and petrographic (thin section, epifluorescent, fracture-focused, and SEM) data, and a combination of XRD mineralogy and organic petrology provide the opportunity to evaluate multiple reservoir quality indicators across several depositional and diagenetic facies. Linking diagnostic indicators to specific facies (and providing constraints on the likely variation within) rather than simply associating these properties with broader stratigraphic intervals should enhance our ability to predict naturally inherent variations in the formation which will improve lateral well placement and completions strategies. It is anticipated that the data gathered, and the interpretations made from it will be used to design and alter the development and completion strategies across the asset to increase production and reduce risk.