井下可视化自动寻航钻井技术初探

针对地层模型预测不准确、钻头处地层特性分析不到位和地层边界确定不及时等影响优质储层钻遇率问题，开展了可视化寻航钻井探索性研究。该技术包括井周地层预测及三维可视化、导航模型构建、地层边界自动分析、地层特性实时自动分析、优质储层自动识别和轨迹自动优化等几个过程。前3个过程属于可视化导航地层模型构建，用于宏观上预测和指示富集油气目标地层位置、延展性等；地层边界自动分析、地层特性实时自动分析及优质储层自动识别用于精细预测钻头附近地层的边界位置、实时提供地层的岩性、物性和含油性，以便精确确定钻进方向；轨迹自动优化则用于自动规划下一步钻井方案。在多口井现场应用中，该系统预测的地层模型及优化的轨迹提高了优质储层钻遇率。结果表明，井下可视化自动寻航钻井技术能够在一定程度上实现类似于汽车导航式钻井，为提高优质储层钻遇率提供了一种新的技术手段。

Exploration a Downhole Visual Automatic Seeker Drilling Technology

Compared with traditional geological steering drilling, automatic seeker drilling is capable of automatic seeker information collection, which is the goal that drilling operators have been pursuing. The automatic navigation technology mainly includes several processes, such as formation prediction around wells and three-dimensional visualization, navigation model construction, automatic identification of stratigraphic boundary, and formation characteristics, automatic identification of highquality reservoirs and automatic optimization of trajectory. The first three processes consist of the construction of visual navigation stratum model, which can be used to make macroscopic prediction and indication of the location and ductility of oil and gas enrichment target stratum; automatic identification of stratigraphic boundary, real-time automatic analysis of stratum characteristics and automatic identification of high-quality formation for precise prediction of the boundary position of stratum near drill bit, and to provide real-time lithology, physical properties and oil-bearing property of stratum, so as to accurately determine the drilling side; the automatic trajectory optimization used for automatic plan for the next drilling plan. The implementation of this technology requires the combination of near-bit gamma-ray and far-detection resistivity instruments. The technology has been applied successfully, and the navigation model formed is basically consistent with the actual drilling strata. The application results show that the downhole visual automatic seeker drilling technology provides a new technical means for high-speed drilling construction and improving the drilling rate of high-quality reservoirs.