Seismoelectric Characterization Of The Vadose Zone

ZYSERMAN, FABIO IVÁN; LEONARDO MONACHESI; LAURENCE JOUNIAUX

Strasbourg, France

Congreso; FlowTrans2015 : International Conference on Flow in Transforming Porous Media,; 2015

ITN FlowTrans, IPGS / CNRS, EOST / Université de Strasbourg

We study seismoelectric conversions generated in the vadose zone, when this region is traversed by a pure SH wave. We assume that the soil is a partially saturated one dimensional porous media where water flow obeys Richards? equation, and we use the van Genuchten constitutive model to compute the water saturation as a function of pressure height. Correspondingly, we extend Pride?s formulation as suggested by Warden et al. [4] to deal with the described conditions, introducing two different saturation dependent functions, namely one monotonous [5] and a non monotonous one [6] into the electrokinetic coupling coefficient. We consider different soil textures and analyse how they affect, among other relevant properties, the electrokinetic coupling coefficient and interface responses, and observe that the latter are several order of magnitude stronger than the coseismic signal, contrary to what happens in the P-wave case.