Addressing the Challenge of Low UCS Core Acquisition using Novel PSWC Technology and Digital Rock Physics

Summary In the pursuit of cost-effective reservoir characterization strategies, a new percussion sidewall coring technology was developed to specifically address poor core recoveries observed in soft, low unconfined compressive strength (UCS) formations often encountered in the energy industry. Conventional full-bore core acquisition usually performs well in soft formations but can be costly due to the drill string trip times required. Rotary sidewall coring on wireline is a faster, often cheaper method that can work well in firm to hard formations, but which often disappoints in soft formation. Percussion sidewall coring typically works well in those conditions, but samples thus obtained often suffer from penetrative damage, rendering them less useful for accurate subsurface characterization. This paper presents a novel method of percussion sidewall core acquisition designed to minimize such damage, thereby providing intact samples of reservoir material suitable for comprehensive subsurface workflows. Benchmarking and validation workflow established through digital rock physics are also presented, alongside the preliminary analysis of subsurface plugs obtained using this advanced methodology in a recent field trial.