Improved Pressure Coring System for Fluid Content Measurements

摘要

An improved tool for obtaining cores under near in situ conditions for accurate fluid content measurements is described. Applications concern the determination of the saturations of tight gas sands and unfractured shales. In addition, oil reservoirs, both new and those in secondary or tertiary recovery stages, will benefit. Three separate areas of system improvement research are discussed: (1) incorporation of a low-invasion fluid that is stored in the core retriever and is extruded to seal and protect the core; (2) the design of a diamond bit with features to reduce fluid invasion and increase penetration rate, and (3) mechanical changes to allow the taking of larger diameter cores with greater reliability. The system developmental progression, which utilizes laboratory coring tests to confirm design ideas, is also discussed. (ERA citation 03:056480)