摘要
介绍了Hudson裂缝介质模型;阐述了边界元法的基本原理;建立了纵波在裂缝介质中传播的边界元法数值模型;模拟了裂缝密度、裂缝纵横比和裂缝填充物对纵波的传播速度和衰减因子的影响;分析了Hudson理论中裂隙参数的有效取值范围以及可能带来的误差。模拟结果表明,边界元法可以很好地模拟含裂缝非均匀介质中波的传播问题,裂缝密度对纵波传播速度和衰减因子有一定的影响。在地震长波长情况下,相同特征尺度的圆形干裂缝比薄形干裂缝对弹性波的散射可以进行更有效的衰减;裂缝饱和充水后各向异性程度下降,且纵横比值越小,岩石介质性质对裂缝流体越敏感。
The Hudson fracture medium model is introduced, the basic principle of boundary element method is elaborated, the boundaryelement-based numerical model of P-wave transmitting in the medium of fractures is established, the influence of density, aspect ratio , and filling materials of fractures on propagation velocity and decay factor of P-wave is stimulated, and the valid span of fracture parameters and possible error in the Hudson theory is analyzed. The result shows that 1) the boundary element method can well stimulate the wave transmitting in a heterogeneous medium such as fractures, 2) the density of fractures have a certain influence on the propagation velocity and decay factor of P-wave, and on the condition of long wavelength, the circular sun cracks with the same characteristic dimension are more effective in scattering of elastic wave than the thin sun cracks, and 3) the anisotropy degree of fractures decreases when it is saturated with water, and the less the aspect ratio is , more sensitive to fracture fluid the rock will be.
出处
《石油物探》
EI
CSCD
2006年第5期435-440,共6页
Geophysical Prospecting For Petroleum
基金
国家自然科学基金项目(40574056)资助。
关键词
裂缝介质
边界元法
各向异性
弹性波
裂缝密度
fracture medium
boundary element method
anisotropy
elastic wave
crack density
