Semi-brittle rheology and ice dynamics in DynEarthSol3D

We present a semi-brittle rheology and explore its potential for simulating glacier and ice sheet deformation using a numerical model, DynEarthSol3D (DES), in simple, idealized experiments. DES is a finite-element solver for the dynamic and quasi-static simulation of continuous media. The experiments within demonstrate the potential for DES to simulate ice failure and deformation in dynamic regions of glaciers, especially at quickly changing boundaries like glacier termini in contact with the ocean. We explore the effect that different rheological assumptions have on the pattern of flow and failure. We find that the use of a semi-brittle constitutive law is a sufficient material condition to form the characteristic pattern of basal crevasse-aided pinch-and-swell geometry, which is observed globally in floating portions of ice and can often aid in eroding the ice sheet margins in direct contact with oceans.