一种计算岩石基质压缩系数的方法

A Method for Calculating the Compressibility Coefficient of the Rock Matrix

未晛 殷晗钧

WEIXian YINHanjun

中国石油勘探开发研究院, 北京 海淀 100083 中国石油大学(北京)地球物理与信息工程学院, 北京 昌平 102249

Research Institute of Petroleum Exploration & Development, PetroChina, Haidian, Beijing 100083, China College of Geophysics and Information Engineering, China University of Petroleum(Beijing), Changping, Beijing 102249, China

建立储层物性、含流体性与弹性参数之间的关系是储层预测与烃类检测的基础。在利用Biot-Gassmann方程研究含不同流体岩石弹性性质时，岩石基质压缩系数的快速、准确求取非常关键。基于一个合理的假设，利用Biot-Gassmann方程推导出了一种计算岩石基质压缩系数的方法，并用干燥、水饱和并且取芯来自同一砂岩层的致密砂岩的高、低频实验数据对本方法的正确性进行验证。结果表明，岩石具有一致的岩石基质压缩系数，该方法有效可靠。受岩石微观孔隙结构和亲水矿物的影响，在不同频率或饱和流体状态下求取的岩石基质压缩系数存在较小差异，在应用过程中需对频率和孔隙流体的影响进行适当考虑。

Establishing the relationship between the physical properties, fluid properties, and elasticity parameters of a reservoir is the basis for reservoir prediction and hydrocarbon detection. When using the Biot-Gassman equations to study the elastic properties of rocks with different fluids, the speed and accuracy of deriving the compressibility coefficient of the rock matrix are critical. Based on reasonable assumptions, the Biot-Gassmann equation was used to derive a calculation method for the rock matrix compressibility coefficient; the method was verified by using dehydrated and saturated and high-and low-frequency experimental data for identical tight sandstone. The results showed that this method is effective and reliable for rocks with identical matrix compressibility coefficients. Due to the influence of the microscopic pore structure and hydrophilic minerals, the derived rock matrix compressibility coefficients display small variations with different frequency and saturation fluids. Therefore, the frequency and pore fluid influence should be considered during the application.

10.11885/j.issn.1674-5086.2016.06.01.02