Application of fast and efficient drilling and completion technology in Gulong shale oil

Abstract:

The Gulong shale oil in the Songliao Basin is a core area for unconventional oil and gas reserve increase in China. It is characterized by well-developed high-quality source rocks， dense nanoscale pore-throat system， abnormally high formation pressure coefficients， and heterogeneous wettability. To address challenges including high wellbore instability， stringent trajectory control requirements， and high torque/drag control difficulty during drilling， we optimized and developed efficient drilling tools， built precise trajectory control models， and refined drilling parameters. We also developed a high-performance oil-based drilling fluid system with strong sealing for nano-pore and fracture formations and a resilient cement slurry system. By integrating these fast-drilling and completion technologies， we achieved efficient development. The average drilling speed increased by 29.5%， the success rate of drilling high-quality reservoirs in horizontal sections reached 90.26%， and the excellent cementing quality rate rose to 90%， ensuring stability and safety in shale oil horizontal well drilling. By establishing a learning curve to modify and improve the block-specific speed-up technical template timely， this study further promotes the speed-up of Gulong shale oil horizontal wells and accelerates the exploration and development.