基于复杂地质建模的地震导向钻井技术及应用

Seismic Guided Drilling Based on the Complex Geological Modeling and Its Application

张希晨 刘晓波 崔京彬 陈茂山 李磊

ZHANG Xichen LIU Xiaobo CUI Jingbin CHEN Maoshan LI Lei

中国石油东方地球物理公司物探技术研究中心, 河北 涿州 072750

Research & Development Center, BGP Inc., CNPC, Zhuozhou, Hebei 072750, China

强构造变形区增加了井眼轨迹设计和施工的难度，容易导致预测深度与实际深度相差甚远，同时，现有的地震导向钻井技术尚未成熟。针对上述问题，提出了基于三维地质建模的地震导向钻井方法及流程，高效准确地完成钻前地质评价、井轨迹设计和钻井实时校正。流程主要分为3个阶段： 1）复杂地质建模，经过设置模型初始参数、断面建模和层面建模，得到精细三维构造模型，在此基础上生成储层敏感属性模型。2）三维井轨迹设计，根据属性模型反映的构造、储层和油气藏特征，并结合钻井工程需求，在三维属性模型设计并拾取井轨迹。3）创建“标志层倒三角逐层逼近法”进行速度深度交互校正，利用施工井新钻遇的标志层深度校正速度体，使深度域三维模型逐渐接近真实地下模型，入靶点预测深度不断接近真实深度，及时指导钻进方向并规避风险。流程在实际应用中取得良好成效，预测深度误差率小于0.2%，工作效率提高5倍。

At present, strong structural deformation aggravates the difficulty of well trajectory design and construction, making the predicted depth far from the actual depth. In addition, the existing seismic steering drilling technology is not yet mature. To solve the above problems, in order to efficiently and accurately complete pre drilling geological evaluation, well trajectory design and real-time drilling correction, this paper proposes a seismic steering drilling method and process based on 3D geological modeling, which is divided into three stages. First, complex geological modeling. After setting initial parameters of the model, section modeling and layer modeling, a fine 3D structural model is obtained, and on this basis, a reservoir sensitive attribute model is generated. Second, 3D well trajectory design. According to the characteristics of structure, reservoir and oil and gas reservoir reflected by the attribute model, and in combination with the needs of drilling engineering, the well trajectory is designed and picked up in the 3D attribute model. Third, create the “marker bed inverted triangle layer by layer approach method” to conduct velocity depth interactive correction, correct the velocity volume through the newly drilled marker bed depth, so that the depth domain 3D model gradually approaches the real underground model, and the predicted depth of the target entry point constantly approaches the real depth, timely guide the drilling direction and avoid drilling risks. The technical process has achieved good results in practical application, the error rate of prediction depth is less than 0.2%, and the work efficiency is improved by 5 times.

10.11885/j.issn.1674-5086.2022.11.06.02