CA地区低渗砂岩动静态弹性模量转换关系研究

在油气开发中，岩石动静态弹性模量转换关系的研究对于储层可压性以及压裂效果评价尤为重要。选取CA地区4口取心井23块岩样开展室内纵横波测量实验和三轴应力实验，建立了纵横波时差关系、纵波时差与体积密度关系，并在此基础上，建立了动静态弹性模量的转换关系模型。利用未参与建模的6块样品做精度对比和可靠性分析，计算的静态杨氏模量和泊松比与实验测量值都分布在对角线45°线上，静态杨氏模量计算的绝对误差平均值为0.623 GPa，泊松比计算的绝对误差平均值为0.022，说明此次实验建立的动静态弹性模量转换关系精度满足生产需要，为评价地层可压性及设计合理的压裂方案提供技术支持。

Study on Dynamic and Static Elastic Modulus Transformation Relationship of Low Permeability Sandstone in CA Area

In oil and gas development, the study of dynamic and static elastic modulus transformation relationship of rock is very important for the evaluation of reservoir compressibility and fracturing effect. In this paper, we use 23 rock samples from 4 coring wells in CA area to carry out P-wave and S-wave measurements and triaxial stress tests, and the relationship between P-wave and S-wave time difference, longitudinal wave time difference and volume density was established. On this basis, the transformation relationship model of dynamic and static elastic modulus was established. Six samples not involved in modeling were used for precision comparison and reliability analysis. The calculated static Young's modulus and Poisson's ratio were distributed along the 45° diagonal line with the experimental measured values. The average absolute error of the calculation of static Young's modulus was 0.623 GPa, and the average absolute error of the calculation of Poisson's ratio was 0.022. It shows that the accuracy of dynamic and static elastic modulus conversion relationship established in this experiment meets the production needs and provides technical support for evaluation of formation compressibility and design of reasonable fracturing scheme.