三维地质建模技术在水平井钻井地质设计中的应用

Application of 3D geological modeling technology in geological design of horizontal well drilling

目前水平井钻井地质设计依据常规地质认识在一维平面图上的数据分布和测井数据归一化处理的储层解释基础上,通过绘制地质图件寻找有利储层进行水平井轨迹的部署,针对该方法存在的不足,采集经过测井处理的高精度井数据和地震解释处理的地层构造数据,利用三维地质建模技术的随机模拟计算方法,对水平井部署区块建立三维构造模型、岩相模型及属性参数模型,预测储层垂向深度及其中目的层的展布规律和地层倾角的变化,最终用于优化风险区块水平井轨迹的设计。以四川盆地川东风险开发区为例,详细介绍了水平井地质设计流程,并针对地层倾角变化较大的地层,将常规水平井地质设计与基于三维地质建模技术的水平井地质设计方法进行了比较,结果表明,三维地质建模技术能精准预测地层倾角和水平井地质设计中各靶点的垂深,提高地质设计的效率和精准度,利于提高储层钻遇率。

The geological design of horizontal well drilling is currently based on conventional geological knowledge based on the data distribution on a one-dimensional plan and the normalized reservoir interpretation of logging data,and the horizontal well trajectory is deployed by drawing geological maps to find favorable reservoirs.Aiming at shortcomings of this method,by collecting high-precision well data processed by logging and stratigraphic structure data processed by seismic interpretation,and using the stochastic simulation calculation of 3D geological modeling technology,3D structural model,sedimentary facies model and attribute parameter model for horizontal well deployment block are established to predict the vertical depth of reservoir,the distribution law of the target layer and the change of formation dip,and ultimately optimize the design of horizontal well trajectories in risk blocks.Taking the rick development zone in eastern Sichuan Basin as an example,geological design process of horizontal wells is introduced in detail,and the geological design of conventional horizontal wells is compared with the ones based on 3D geological modeling for formations with large changes in stratum dip.Results show that 3D geological modeling technology can accurately predict the formation dip and the vertical depth of each target point in horizontal well geological design,improve the efficiency and accuracy of geological design,and increase reservoir drilling rate.