中文摘要：

弹性阻抗反演属于叠前反演，能够反映振幅随偏移距或入射角的变化，可以获得纵波速度、横波速度、密度、泊松比以及拉梅系数等多种岩性参数。目前，弹性阻抗反演的常规算法为广义线性反演，该反演方法强烈依赖初始模型，容易陷入局部极小。为此，尝试将一种优秀的非线性算法——混沌蚁群算法应用于弹性阻抗反演中，该算法具有能达到全局最小，不依赖初始模型等优点。模型测试证明了混沌蚁群算法的稳定性和可靠性。将基于混沌蚁群的弹性阻抗反演方法应用于胜利油田某储层，其反演结果与实际钻探及测井解释相一致，验证了该反演方法的可行性和有效性。

英文摘要：

As a pre-stack inversion, elastic impedance inversion not only characterizes amplitude variation with offset or inci- dent angle, but also offers more lithologic parameters, such as P-wave velocity, S-wave velocity, density, Poisson s ratio, Lame coefficient etc. However, the common elastic impedance inversion algorithms are generalized linear methods, which are strongly dependent on initial model and easily fall into local minimuro. A good nonlinear algorithm, chaos ant colony algo- rithm, is introduced to elastic impedance inversion in this paper. The chaos ant colony algorithm is model-independent and a- ble to reach global minimum. Model test has demonstrated the reliability and stability of the algorithrrL The inversion results of a res- ervoir in Shengli Oilfield are consistent with the drillin~g data,which proves the feasibility and effectiveness of the method.