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侧向电阻率测井由于具有较好的探测深度和较高的纵向分辨率而成为油储地球物理测井中的一种重要方法，是确定储层中油气含量的最主要手段．然而，当地层的厚度小于其纵向分辨率时，由于受井眼泥浆和上下围岩等的影响，实测的视电阻率已无法反映地层电阻率的真实变化，给油气层的划分及油储层的定量评价带来了极大的困难，因此，研究侧向电阻率测井反演不论在理论上还是实际应用上均有非常重要的意义．本文首先通过摄动原理给出了层状介质中侧向电阻率测井的Ｂｏｒｎ近似解，并应用混合法得到的电场半解析解，研究了快速计算Ｂｏｒｎ近似的新方法，然后通过拟牛顿法给出了逐步修改地层模型的迭代反演算法．为证明该方法的有效性，以大庆的高分辨率三侧向测井仪为例，给出了理论模型与实际井场资料的处理结果．
Lateral resistivity logging is an important method in oil geophysical logging because of its good exploration depth and high vertical resolution. It is the most important method to determine the oil and gas content in a reservoir. However, when the thickness of the formation is less than its vertical resolution, the measured apparent resistivity can not reflect the real change of the resistivity of the formation due to the influence of borehole mud and surrounding rock. Therefore, it is very important to study the lateral resistivity log inversion whether it is in theory or in practice. In this paper, the Born approximation solution of lateral resistivity logging in layered media is first given by perturbation principle. The semi-analytical solution of electric field obtained by hybrid method is used to study the new method of fast computing Born approximation. Then, An iterative inversion algorithm for gradually modifying the formation model is given. In order to prove the effectiveness of the method, taking Daqing high-resolution three-lateral logging tool as an example, the theoretical model and actual well site data processing results are given.