A Cementing Technology for Shale Oil Horizontal Wells

Organic rich dark shale of Q Formation can be found in many areas (e.g., in the North of S Basin). The shale target stratum is easy to hydrate and often undergoes spallation. Therefore, centering the casing in the horizontal section of the irregular borehole is relatively difficult. Similarly, achieving a good cement flushing efficiency under complex borehole conditions is a complex task. Through technologies such as centralizer, efficient preflushing, multi-stage flushing and ductile cement slurry, better performances can be achieved. In this study, it is shown that the cementing rate in the DY2H horizontal section is 97.8%, which is more than 34% higher than that of adjacent wells. This cementing matching technology for sidetracking horizontal wells can be used to improve the cementing quality of continental shale and provides a reference for future applications in this field.