The research of actual core rocks mechanical parameters and ultrasonic testing has been carried out in consideration of the formation confining pressure, lithology and fluid saturated conditions. The results show that the static Poisson ratio in mudstone is greater than that in sandstone, and the differentiation is greater under the uniaxial condition than that under the confined condition. With the same lithology and the fluid saturated condition, the static Poisson ratio under the confining pressure condition is larger than that under the uniaxial condition and with the increasing of confining pressure, the increase of static rock Poisson ratio in sandstone is larger than that in shale. Under the uniaxial conditions, the P-wave in water saturated rocks is 10% - 15% lager than that in gas saturated rocks, the shear wave is totally the same and the dynamic Poisson's ratio in water saturated rocks is 30% lager than that in gas saturated rocks. Under the confining pressure condition, the velocity of P-wave and S-wave in water saturated rock samples increases when the confining pressure increases, the increase of P-wave velocity is smaller than that of S-wave velocity, the P-wave and S-wave velocity ratio decreases when the confining pressure increases, and the dynamic rock Poisson ratio decreases. The new model of logging interpretation formula for rock Poisson ratio has been established under the condition of simulating the formation confining pressure and fluid and distinguishing sandstone and mudstone.%在考虑地层围压、岩性及饱和流体介质条件下,开展井下岩心力学参数及超声波测试研究.研究结果表明,泥岩静泊松比均大于砂岩静泊松比,且单轴条件下二者差别大于围压条件下；围压条件下相同岩性、相同饱和流体介质的岩石静泊松比大于单轴条件下岩石静泊松比,且随着围压的增大,砂岩静泊松比的增幅大于泥岩.单轴条件下,同岩性饱和水岩样相比饱和气岩样的纵波速度增幅在10％～15％,横波基本无变化,动泊松比增幅在30％以上.围压条件下,饱和水岩样的纵横波速度随围压的增大而增大,纵波速度的增幅略小于横波速度,纵横波波速比随围压的增大而减小,岩石的动泊松比减小.在模拟地层围压和流体条件及区分砂岩、泥岩的前提下,建立了岩石泊松比测井计算模型.
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