Geoscience-engineering integration-based formation damage control drill-in fluid (GEI-FDC-DIF): An essential technology for successful extraction of deep mid-high permeability sandstone reservoirs

Abstract

The impact of drilling-induced formation damage is often underestimated in deep mid-high permeability reservoirs, largely due to modest reductions in permeability reported by conventional evaluation methods. This study introduces an innovative geoscience-engineering integration-based formation damage control drill-in fluid (GEI-FDC-DIF) technology, specifically developed to mitigate the challenges posed by deep wells with open-hole completions. Utilizing comprehensive geological and engineering analyses, our methodology facilitates a multiscale space-time evaluation of formation damage, enabling precise quantification of its severity and evolution. Based on identified mechanisms, tailored GEI-FDC-DIF formulations and supporting process measures are developed to optimize formation damage control. Preliminary geological and engineering evaluations of the deep mid-high permeability sandstone reservoir highlight the acute risk of drilling-induced formation damage. Detailed quantitative analysis indicates fluid sensitivity and drill-in fluid induced permeability reductions ranging from 1.13% to 44.54% and 26.47%–65.55%, respectively, with absolute permeability declines extending into the hundreds of millidarcys. Invasion depths of drill-in fluids reach 3.9–56.6 m at 150 h and 7.6–92.6 m at 840 h, underscoring significant formation damage predominantly caused by solid plugging, fluid sensitivity, incompatibility, and oil phase permeability reduction. Incorporating a blend of acid-soluble fiber bridging, oil-soluble deformable temporary plugging agents, and liquid drainage enhancers, the GEI-FDC-DIF significantly improves plugging efficiency and filtrate flowback. The development and deployment of GEI-FDC-DIF have shown superior formation damage control capabilities, as corroborated by both laboratory and field applications, underscoring its promising potential for future use.