Porosity and permeability estimation using seismic wave velocity along Yangtze River embankment

Abstract

Although porosity and permeability are essential parameters for slope stability, estimating the spatial porosity and permeability variation of slope site is difficult because of complexity of petrophysical modeling. The differential effective medium (DEM) and self-consistent approximation (SCA), which used to calculate elastic modulus of porous materials, are applied to link seismic wave velocity to porosity and permeability. The shear-wave velocity structure is gathered through a near surface Rayleigh-wave survey, and the porosity and permeability profiles are further estimated. The results are cross validated by the borehole data and poroelastic relation. The petrophysical structure of the Yangtze River embankment may further reflect hydrological properties of laminated layers, which bear relatively large porosity and permeability in some area. The results show that the porosity and permeability profiles based on SCA are more reliable with respecting to the borehole data. The relationship between seismic velocity and porosity and permeability is established and validated, favoring a sound basis for further hydrological interpretation of seismic data. Furthermore, some geotechnical suggestions are put forward during the flood seasons in correspondence to the natural hazard mitigation.