由严格的电磁理论出发,分析不同仪器结构探测信号的方位敏感性和对电阻率各向异性的敏感性,结合目前主要方位电磁波仪器设计,提出倾斜发射-倾斜接收的仪器结构,分析该仪器结构的信号测量特征、地质导向能力与各向异性评价能力.针对仪器测量信息,建立距地层界面距离反演算法,实现仪器距地层界面距离与地层电阻率的实时反演.理论与测试结果表明:倾斜发射-倾斜接收的仪器结构具有良好的方位敏感性,地质信号响应(相位差与幅度比)与仪器距界面距离具有良好的线性关系,可以实现任意地层条件下仪器与地层相对倾角、方位角、水平电阻率与垂直电阻率反演.新型仪器能很好地为地质导向与地层评价提供技术支持.%Starting from the sensitivity analysis of instrument's response to geological boundaries and anisotropic resistivity, a tilted-transmitter-and-tilted-receiver structure is proposed in this paper to improve directional measurement as well as anisot-ropy detection.The depth of investigation (DOI) of the tool is analyzed to evaluate the measurements'sensitivity to formation boundary in a certain environment.Inversion algorithm is also developed to achieve real-time processing of the data.As the products of the inversion application, distance to boundaries (DTB), horizontal and vertical resistivity are provided to aid in geosteering and formation evaluation.Inversion results show that the proposed structure is efficient and reliable in providing directional information, is capable of real-time derivation of relative dip angle, azimuth, formation horizontal and vertical re-sistivity inversion in arbitrary borehole environments.
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