裂隙扭曲度对弹性波频散和衰减的影响研究  

Study on the Influence of Fracture Distortion Degree on the Dispersion and Attenuation of Elastic Wave

作　　者：杨俊杰 高启 许可 朱伟[1] YANG Junjie;GAO Qi;XU Ke;ZHU Wei(College of Geophysics and Petroleum Resources,Yangtze University,Wuhan 430100,China)

机构地区：[1]长江大学地球物理与石油资源学院,湖北武汉430100

出　　处：《河南科技》2024年第24期90-95,共6页Henan Science and Technology

摘　　要：【目的】研究裂隙扭曲度对弹性波频散和衰减的影响,揭示裂隙几何形态变化与弹性波传播特性之间的内在联系。【方法】针对裂隙扭曲度变化对喷射流效应的影响进行了具体分析。采用广义麦克斯韦型本构方程近似牛顿型流体的本构方程,利用动态应力应变模拟计算了垂直裂隙走向方向上弹性波的频散和衰减。通过数值模拟揭示了不同扭曲度下弹性波的频散和衰减行为,并总结了裂隙几何形态变化对频散特征的影响规律。【结果】随着扭曲度的增大,衰减的特征频率和峰值均减小;速度与扭曲度在低频区呈正相关,在高频区呈负相关。【结论】裂隙扭曲度对弹性波的喷射流效应具有较大影响,实际资料解释中应给予重视。[Purposes]The effect of fracture distortion on the dispersion and attenuation of elastic waves is studied,and the intrinsic relationship between the fracture geometry and the propagation characteristics of elastic waves is revealed.[Methods]In this paper,the influence of fracture distortion on jet stream effect was analyzed.The generalized Maxwell constitutive equation is used to approximate the Newtonian fluid constitutive equation,and the dynamic stress-strain simulation is used to calculate the elastic wave dispersion and attenuation in the vertical fracture direction.The numerical simulation reveals the elastic wave dispersion and attenuation behavior under different distortion degrees,and the influence of fracture geometry on the dispersion characteristics is summarized.[Findings]With the increase of distortion degree,the characteristic frequency and peak value of attenuation decrease.Velocity and distortion are positively correlated in the low frequency region and negatively correlated in the high frequency region.[Conclusions]The distortion degree of fracture has great influence on the jet stream effect of elastic wave,which should be paid attention to in the interpretation of actual data.

关 键 词：动态应力应变模拟 数字岩心 扭曲度 喷射流 弹性波 

分 类 号：P631[天文地球—地质矿产勘探]