Abstract: Only after obtaining the true data about formation anisotropy anisotropic drilling characteristics of the formation can be used scientifically in drilling operations.This paper presents a physical model for evaluating formation anisotropy,which is in the inverse mode of a rock-bit-formation interaction model.Combined with a BHA analysis program,this model can be used to esttimate formation anisotropy from field drilling data.Such a method of assessment can be readily used by field engineers.

摘要： 只有正确地了解地层的各向异性性质,才能在钻井过程中科学地利用这一特性.本文根据钻头与正交各向异性地层相互作用模型,导出了反演计算地层各向异性的物理模型.将该模型与下部钻具组合分析程序相结合,便可利用井史资料定量评估所钻地层的各向异性性质,评估方法简单易行,便于现场应用.

关键词: 地层各向异性, 岩石可钻性, 定向井, 井眼轨迹控制