Correlation of fractures with seismic radial anisotropy in two metamorphic-igneous and sedimentary bedrocks

Fractures strongly affect the hydraulic properties of rocks as they often serve as preferential flow paths for fluids. Therefore, the characterization of subsurface fractures is crucial to understand fluid flow in the geological environments. Seismic radial anisotropy that is defined with respect to the difference between the velocity of a vertically polarized S-wave (SV) and one polarized horizontally (SH) can be used as a strong attribute for forecasting near surface fractures. We evaluate the correlation of seismic radial anisotropy with near-surface fractures. We obtain seismic radial anisotropy models at two sites with different bedrock geologies (one metamorphic-igneous and the other sedimentary) using dispersion analyses of the Rayleigh wave, for vertical polarization, and Love wave, for horizontal polarization. The seismic radial anisotropies at these two sites show a strong correlation with near surface fractures.