基于气体包裹体模型的低孔低渗储层声波速度研究

随着石油勘探工业的持续发展和技术水平的日益提高，低孔低渗油气藏已成为我国油气勘探开发的重要领域之一，但是该类油气藏的储层岩石物理关系复杂，对其评价也相对较难。本文针对中深层气藏低孔低渗储层评价存在的困难，采用修正的White气体包裹体模型开展岩石物理研究。首先对气体包裹体模型进行分析，得到纵横波速度的计算公式，进而理论计算并分析纵横波速度与孔隙度、饱和度、压力及温度参数的变化关系，最后结合岩心实验对理论计算结果进行了验证。研究结果表明基于气体包裹体模型的理论计算结果与实测数据吻合较好，可以较好地为低孔低渗复杂储层声波速度测量及解释提供技术支持。 

Acoustic Velocity Study of Low Porosity and Low Permeability Reservoir Based on Gas Inclusion Model

According to the evaluation difficulty of middle-deep gas reservoir with low porosity and low permeability, the study of rock physics using modified White gas inclusion model is carried out in this paper. Firstly, the gas inclusion model is analyzed to get the calculation formula of P-wave and S-wave velocity. Then, the parameters of acoustic velocity, porosity, saturation, pressure and temperature are theoretically calculated. Finally, the calculated results are verified by laboratory experiments. This study indicated that P-wave velocity changed obviously with the water saturation variation, and S-wave velocity changed slightly with the water saturation variation. Compaction makes the P-wave velocity increases rapidly and the S-wave velocity increases slowly, which is caused by the changes of elastic modulus and shear modulus. Effect of temperature on the acoustic velocity can be neglected. The study of this paper can provide technical support for the acoustic wave velocity measurement and interpretation of complex reservoir with low porosity and low permeability.