Slideshow:  Start | Stop
«  |   Home  |   »

Object name Pressure Ridges
Caption Many glacial sources coalesce to form the huge mass of the Ross Ice Shelf, more than 300,000 square miles — roughly the same area as France. This mass of ice averages 1,000 feet thick, increasing to a maximum of 2,500 feet. Underneath is an ocean that is subject to tides and currents. Where the ice shelf is joined to land the tides and other ocean currents cause immense cracks or crevasses called pressure ridges. From a distance they look like huge waves about to break on the shore. These “waves” buckle under the pressure. Up close (see next photo) they can stand up to 15 feet high.
Copyright notice © Irma Hale