渤海油田裂缝性油藏地质工程一体化井漏预警技术

为了解决渤海油田裂缝性油藏钻井过程中因断层、裂缝引起的井下漏失等问题，提出了地质工程一体化井漏预警技术。在叠后地震大中尺度断层刻画的基础上，通过滤波、断裂增强等特殊处理，进行属性优选及多属性融合，精细刻画中小尺度裂缝，建立了多尺度裂缝三维空间分布模型，设计井眼轨道时避开漏层，进行钻前风险提示，指导钻井作业采取相应的防漏堵漏措施；钻进过程中开展井漏风险随钻跟踪，实时调整并反馈井漏风险预测结果，及时优化井眼轨道，形成了随钻过程中漏层动态避钻技术，以充分保障钻井作业安全，降低钻井成本。钻前风险预测、钻进中井漏跟踪及随钻井眼轨迹实时优化等技术在旅大X油田应用后，实现了一趟钻规避断层漏失段。地质工程一体化井漏预警技术能够降低钻井风险，保障裂缝性油藏的钻井安全，为渤海油田增储上产提供了技术支撑。 

Integrated Geology-Engineering Early Warning Technologies for Lost Circulation of Fractured Reservoirs in Bohai Oilfield

In order to solve the problems of downhole leakage caused by faults and fractures in the drilling process of fractured reservoirs in Bohai Oilfield, integrated geology-engineering early warning technologies for lost circulation were proposed. Using large and medium-scale fault characterization in post-stack seism, special treatments such as filtering and fault enhancement were carried out to optimize attributes, fuse multiple attributes, finely describe small and medium-scale fractures, and a three-dimensional spatial distribution model of multi-scale fractures was established. In the design of the wellbore trajectory, drilling in the layers with leakage was avoided. The model was used to develop risk warnings before drilling and guide drilling operations in taking countermeasures for preventing and plugging leakage. During the drilling process, the tracking technology for lost circulation risk was implemented, and the prediction results of the risk were adjusted and fed back in real time. As a result, the wellbore trajectory was optimized in a timely manner, and a dynamic technology for avoiding layers with leakage while drilling was formed, which fully guaranteed the safety of drilling operations and reduced operating costs. The above-mentioned technologies such as risk prediction before drilling, tracking for lost circulation during drilling, and real-time optimization of the wellbore trajectory while drilling were successfully applied in Lvda X Oilfield and avoided leakage sections of the faults in one trip. The integrated geology-engineering early warning technologies for lost circulation can effectively minimize drilling risks and ensure operational safety in fractured reservoirs, which provides technical support for increasing reserves and production of Bohai Oilfield.