Conductivity dependence of seismoelectric wave phenomena in fluid‐saturated sediments

Abstract

[1] Seismoelectric phenomena in sediments arise from acoustic wave-induced fluid motion in the pore space, which perturbs the electrostatic equilibrium of the electric double layer on the grain surfaces. Experimental techniques and the apparatus built to study the conductivity dependence of the electrokinetic (EK) effect are described, and outcomes for studies in loose glass microspheres and medium-grain sand are presented. By varying the NaCl concentration in the pore fluid, we measured the conductivity dependence of two kinds of EK behavior: (1) the electric fields generated within the samples by the passage of transmitted acoustic waves and (2) the electromagnetic waves produced at the fluid-sediment interface by the incident acoustic wave. Both phenomena are caused by relative fluid motion in the sediment pores; this feature is characteristic of poroelastic (Biot) media but is not predicted by either viscoelastic fluid or solid models. A model of plane wave reflection from a fluid-sediment interface using EK-Biot theory leads to theoretical predictions that compare well to the experimental data for both loose glass microspheres and medium-grain sand.Citation: Block, G. I., and J. G. Harris (2006), Conductivity dependence of seismoelectric wave phenomena in fluid-saturated sediments,

Laboratory measurements and theoretical modeling of seismoelectric interface response and coseismic wave fields

“…[3][4][5][6][7] Furthermore, a wide range of field and laboratory validations of the coseismic field and the interface response was presented in the literature. [8][9][10][11][12][13][14][15][16][17][18][19][20][21] Several of these works compare either field measurements 15,17 or laboratory measurements 20 with a seismoelectric wave propagation model, corroborating that the coseismic and interface response fields are predicted by the theory.…”

Measurements of the Relationship Between Microstructure, pH, and the Streaming and Zeta Potentials of Sandstones

“…(Sprunt et al 1994;Pozzi 1995a, 1997;Li et al 1995;Jiang et al 1998;Pengra et al 1999); [2] sandstone with NaCl as a function of permeability/microstructure (pH5) (Jouniaux and Pozzi 1995b); [3] St. Bees, Stainton, and Fontainebleau sandstones with NaCl (Jaafar et al 2009;Vinogradov et al 2010); [4] sandstone with KCl (Alkafeef and Alajmi 2007); [5] sand with NaCl (Guichet et al 2003;Block and Harris 2006);[6] granite with NaCl (Morgan et al (1989)); [7] glass with NaCl (Pengra et al 1999;Block and Harris 2006);[8] zeolitized tuffs with NaCl (Revil et al 2002);[9] basalt with NaCl (Revil et al 2003 (Tardif et al 2011;Glover et al 2012a). b [1] Quartz with NaCl (Pride and Morgan (1991)); [2] silica with NaCl (Gaudin and Fuerstenau 1955;Li and Bruyn 1966;Kirby and Hasselbrink 2004);[3] glass beads with NaCl (Bolève et al 2007);[4] St.…”

A review on electrokinetically induced seismo-electrics, electro-seismics, and seismo-magnetics for Earth sciences

“…Recording of the electrodes: the simultaneous wave arrival in water and sand is the interfacial response, and the move out signal is related to the transmitted wave. The water conductivity is 0.0076 S m −1 (from Block and Harris, 2006). bulk conductivity (Fig.…”

“…Another study was performed, by Block and Harris (2006), on sand to detect the interfacial response between water and saturated sand. The experimental set-up developed is a cylindrical PVC tube (2 m height), with nine Ag/AgCl electrodes.…”