CONTINUUM MECHANICAL MODELING OF THE DISSIPATIVE PROCESSES IN THE SEDIMENT-WATER LAYER BELOW GLACIERS

The solid mass of the saturated viscous, heat-conducting sediment-wate r layer below temperate glaciers grows by abrading the underlying rock bed. We propose to model this laver as a saturated mixture continuum o f fluid and solid. We formulate its balance laws in volume and jump lo cal forms following, e.g. Germain and Muller (1986). The water balance accounts for its drainage into the rockbed and the melting of ice wit hin the overlaid ice sheet. Dissipation due to the power expended by s tresses, the Darcy interaction force and sliding friction governs this thermomechanical system. Our analysis establishes that, contrary to w hat is stated in the literature, the listed dissipative mechanisms are all relevant.