基于人工鱼群算法和SCA等效理论的井中横波速度预测方法

摘要

Based on the rock physics model of shale, according to the rock physics model of equivalent self consistent approximation(SCA),the authors build the quantitative relationship between P-wave, S-wave and the rock density,rock composition and rock porosity to find a pore aspect ratio can minimize the error of the theoretical P-wave velocity and the actual P-wave velocity.Then the authors use this pore aspect ratio as the constraint condi-tion to achieve the prediction of shear wave velocity.The inversion algorithm uses the artificial fish swarm algorithm to calculate the optimal aspect ratio,and compares the predicted shear wave velocity with the actual measured shear wave velocity which proves the effectiveness of the artificial fish-swarm algorithm.%在建立页岩岩石物理模型的基础上,根据等效自相容近似(SCA)岩石物理模型,构建出岩石的纵波速度、横波速度与岩石密度、组分和孔隙度等的定量关系,得出使理论纵波速度和实际纵波速度最接近的孔隙纵横比,进而将该孔隙纵横比作为约束条件来实现横波速度预测.反演算法利用人工鱼群算法来计算最佳孔隙纵横比,并将预测的横波速度与实际测得的横波速度对比,证明了人工鱼群算法的有效性.