Static elastic properties, derived from stress–strain data, and dynamic elastic properties, derived from P- and S-wave velocities, are significantly different for rocks. Most rocks are deformed nearly statically (due to tectonic forces and reservoir compaction during production of the reservoir) but static measurements are not as readily available as dynamic measurements. Hence, empirical relationships between the static and dynamic elastic properties are needed to convert the dynamic elastic properties to static values. In this study, the static and dynamic Young’s moduli and Poisson’s ratio were measured simultaneously for dry and fluid-saturated mudstone samples. The samples were axially loaded only within the elastic region to determine the static elasticity. The samples were from four different lithofacies within the Naparima Hill Formation, Trinidad, West Indies. Experiments were carried out at effective pressures up to 130 MPa to determine if the relationship, if any, is influenced by effective pressure. The results show that the dynamic Young’s modulus is greater than the static Young’s moduli. Saturation of the samples causes a decrease in the Young’s modulus and an increase in Poisson’s ratio. Saturation also increases the difference between the static and dynamic Young’s moduli and Poisson’s ratio. A linear relationship with high correlation ( R 2 greater than 0.9) was established between the static and dynamic Young’s moduli. The gradient of the linear relationship increases, while the intercept decreases, with increasing effective pressure and axial loading. No clear trend was observed between the static and dynamic Poisson’s ratio.

中文翻译：

---

有效压力对Naparima Hill组泥岩静态和动态杨氏模量与泊松比关系的影响

岩石的静态弹性属性（源自应力应变数据）和动态弹性属性（源自 P 波和 S 波速度）显着不同。大多数岩石几乎是静态变形的（由于在油藏生产过程中的构造力和油藏压实），但静态测量不像动态测量那样容易获得。因此，需要静态和动态弹性属性之间的经验关系来将动态弹性属性转换为静态值。在这项研究中，同时测量了干燥和流体饱和泥岩样品的静态和动态杨氏模量和泊松比。样品仅在弹性区域内轴向加载以确定静态弹性。样品来自 Naparima Hill 组内的四种不同岩相，特立尼达，西印度群岛。在高达 130 MPa 的有效压力下进行了实验，以确定这种关系（如果有的话）是否受有效压力的影响。结果表明动态杨氏模量大于静态杨氏模量。样品的饱和导致杨氏模量降低和泊松比增加。饱和度还会增加静态和动态杨氏模量和泊松比之间的差异。静态和动态杨氏模量之间建立了具有高相关性（R 2 大于0.9）的线性关系。随着有效压力和轴向载荷的增加，线性关系的梯度增加，而截距减小。在静态和动态泊松比之间没有观察到明显的趋势。在高达 130 MPa 的有效压力下进行了实验，以确定这种关系（如果有的话）是否受有效压力的影响。结果表明动态杨氏模量大于静态杨氏模量。样品的饱和导致杨氏模量降低和泊松比增加。饱和度还会增加静态和动态杨氏模量和泊松比之间的差异。静态和动态杨氏模量之间建立了具有高相关性（R 2 大于0.9）的线性关系。随着有效压力和轴向载荷的增加，线性关系的梯度增加，而截距减小。在静态和动态泊松比之间没有观察到明显的趋势。在高达 130 MPa 的有效压力下进行了实验，以确定这种关系（如果有的话）是否受有效压力的影响。结果表明动态杨氏模量大于静态杨氏模量。样品的饱和导致杨氏模量降低和泊松比增加。饱和度还会增加静态和动态杨氏模量和泊松比之间的差异。静态和动态杨氏模量之间建立了具有高相关性（R 2 大于0.9）的线性关系。随着有效压力和轴向载荷的增加，线性关系的梯度增加，而截距减小。在静态和动态泊松比之间没有观察到明显的趋势。