摘要
多数沉积岩有细长孔隙和裂隙,根据Berryman散射模型方法,采用椭球状孔隙模拟岩石裂隙,通过改变椭球状孔隙的纵横比,可以模拟裂隙的形状。结合Gassmann方程和Walsh公式研究孔隙纵横比对岩石的弹性性质、纵横波速度、流体替换的影响。计算结果表明,对于具有相同矿物成分和孔隙率的岩石,由于裂隙的形状(椭球状孔隙的纵横比)不同,岩石体积模量、孔隙弹性模量、纵横波速度、泊松比都有明显的不同。随着孔隙纵横比的增大,体积模量、孔隙弹性模量呈近似线性增大,泊松比呈非线性减小,纵横波速度增大,流体对岩石物性的影响(流体替换)也减小;反之亦然。
A lot of sedimentary rocks have long and thin pores and fractures. According to Berryman scattering model method, using ellipsoidal pores to simulate the fractures of rocks and through changing the aspect of ellipsoidal pores, the shapes of fractures can be modeled. In combination with Gassmann equations and Walsh formulas, the studying the effects of aspect of pores on elastic property,P-and S-wave velocities and fluid-replacement is conducted. The computational results showed that for the rocks having similar mineral components and porosity, the volumetric modulus of rock, elastic modulus of pores, P-and S-wave velocities and Poisson ratio have distinct difference because of difference of shape of fractures (aspect of ellipsoidal pores). Along with increasing the aspect of pores, the volumetric modulus and elastic modulus of pores approximately linearly increase, Poisson ratio decrease non-linearly ,P-and S-wave velocity increase and influence of fluid on petro-physical property also decreases,vise verse.
出处
《石油地球物理勘探》
EI
CSCD
北大核心
2005年第3期334-338,共5页
Oil Geophysical Prospecting
