Azimuthal anisotropy of seismic velocity, attenuation and Q value in viscous EDA media

By considering the constitution relationship between stress and strain in v iscous EDA media in the domain of frequency, seismic wave equations in the media in the domain of time and space are established. The anelastic effect s induced by cracks or fractures are shown by the third derivatives of disp lacement components with respect to time in the equations. After solving th e equations for the seismic propagation of plane waves, seismic velocity, a ttenuation and quality factor (Q value) are obtained, and their azimuthal a nisotropy in the dry cracked and water saturated cracked EDA media are stud ied. The results show that, seismic velocity, attenuation, quality factor ( Q value), especially attenuation or quality factor ratio of 2 kinds of qS w ave can be used to indicate the existence of oriented cracks and material c ontents in the crack. Meanwhile, elasticity is predominant at low frequency , and anelasticity is significant at high frequency.