Active seismoelectric exploration of glaciers

Abstract

Repeatable and strong seismoelectric signals were recorded on Glacier de Tsanfleuron, Switzerland, using a vertical sounding geometry. Electromagnetic waves are inferred to be generated by electrokinetic conversion of seismic energy within the snow pack and near the dry-wet ice and ice-bed interfaces. A simple gradient-based scheme allows such electrokinetic interface responses (EIRs) to be isolated from noise. EIRs depend sensitively on the azimuthal orientation of the receiving array of electrical dipoles. Seismoelectric techniques promise to allow mapping even of thin water-bearing strata within or beneath glaciers or frozen ground, estimation of hydraulic or fluid properties of such strata, as well as monitoring of ice fracturing or basal properties and processes at improved spatial resolution. Copyright 2006 by the American Geophysical Union.