A Measurement of Surface-Perpendicular Strain-Rate in a Glacier

Abstract

The surface-perpendicular component of velocity and strain-rate have been determined at one site in the ablation area of Blue Glacier, Washington, U.S.A., where the total depth is about 250 m. The strain-rate is near zero at the surface but increases with depth to about 4% a⁻¹ at 175 m. The results were obtained with the help of a finite deformation theory from the measured stretch of cables frozen into the ice.