黔西地区钻遇地层漏失分析及堵漏措施探讨

Leakage analysis and exploration of leakage stoppage measures for drilling strata in western Guizhou

通过对研究区钻遇地层漏失统计分析,显示黔西地区钻遇地层永宁镇组主要为裂缝性漏失、溶洞性漏失,飞仙关组、长兴组为裂缝性漏失,龙潭组为渗透性漏失。研究区灰岩层位建议采用空气钻一开钻穿喀斯特区,用套管封隔漏失层,降低二开钻遇喀斯特风险。砂泥岩频繁互层的地层采用螺杆+PDC钻头复合钻井技术。研究结果可为下一步钻探安全及勘探开发提供一定的指导。

Through the statistical analysis of the lost circulation of the drilled strata in the study area, it is shown that the Yongningzhen formation of the drilled strata is mainly fractured and cavernous, the Feixianguan and Changxing formations are fractured and the Longtan formation is permeable in western Guizhou. The limestone horizon suggests that air drilling should be used to drill through the karst area in the study area, and casing should be used to seal the leakage layer, so as to reduce the risk of karst during the second drilling. The composite drilling technology of screw and PDC bit is used in the formation with frequent interbedding of sand and mudstone. The research results can provide some guidance for drilling safety and exploration and development in the next step.