SHORT NOTES GLACIERS AND ICE-SHEETS: MODERN PROBLEMS AND TECTONIC ASSOCIATIONS

Abstract: Glaciers, and rocks of the Earth’s crust, have a brittle zone (which breaks) above a plastic zone (which flows). The brittle zone is distinguished by crevasses (glaciers) and faults (rocks); the plastic zone by flow structures. Glaciers and ice-sheets such as Greenland and Antarctica flow essentially by creep, and are governed by laws of creep. The surface temperature has negligible effect on flow. Global warming cannot cause a “collapse ” of the ice-caps. The basins of Greenland and Antarctica are, if created by isostatic response to the load of the ice pile, a result of creep in the lower crust or mantle