Bayesian Estimation of Ice Content in a Rock Glacier from P and S Velocities

Rock glaciers are creeping ice-rock mixtures in permafrost environment which may represent significant solid water resources. In the present work the hydrologic importance of rock glaciers in mining districts of Norte Chico, Chile, is studied with seismic and GPR. Compression and shear waves velocities from travel time tomographies are used to estimate the ice content. Using a petrophysical model and Bayesian inversion, Vp Vs seismic velocities are translated into estimated porosities and volumetric fractions of ice, water and air. The average ice content of the rock glacier estimated from seismic data is 29%, in agreement with local ice measurements in a drill hole.