In the drilling of horizontal wells, the core task of surface logging is to guide geosteering while drilling by using collected data including electrical property, lithology, petrophysics, and oil/gas-bearing properties. Surface logging in the horizontal geosteering drilling have two key technologies: one is stratigraphic correlation and prediction technology before encountering the zone of interest, the other one is geological interpretation and geosteering technology after encountering the zone of interest. Based on a systematic analysis of difficult points in the two aspects, in combination with application examples, this paper deeply analyzes how to accurately drill into horizontal section by in-depth stratigraphic correlation and timely model modification in the case of inaccurate horizon depth design; and how to improve drilling-encounter ratio of oil layer and well bore quality by accurate interpretation and guidance in the case of encountering non-target zone (e.g., borehole deviates from right track, sedimentary facies changes in the target zone, faults or mudstone interlayers are encountered.).%水平井钻进过程中,录井的核心任务是利用随钻过程中获得的岩性、电性、物性及含油气性资料进行地质导向.水平井地质导向录井包括两项关键技术:一是进入目的层前的地层对比和预测技术;二是进入目的层后的地质解释与导向技术.通过对这两项技术难点的系统分析,结合应用实例,深入分析了在目的层设计深度不准确的情况下,通过录井精细对比及时修正模型、保证准确进入水平段开采目的层的技术;水平段钻遇非目的层岩性情况下(井眼偏离正确轨迹、目的层沉积相变化、钻遇断层、钻遇泥岩夹层等),可利用随钻测井资料、井区资料、地震剖面等进行精确解释,提出钻头前进方向,保证油气层钻遇率和井身质量.
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