Horns, Aretes, Cirques, southern Greenland The cirques are the bowl-shaped regions at the tops of the glaciers--they are the main ice accumulation areas. The horns are the sharp peaks that are surrounded by cirques; the aretes are the narrow ridges that separate cirques

Tributary Glacier, southern Greenland . The large valley glacier on the left is far more effective at eroding its channel than the smalltributary glacier on the right--when the glaciers retreat, the tributary glacier will leave behind a hanging valley.

Aerial view of active glacial cirque and large valley glacier,Kluane National Park, Yukon, Canada. Mt. Logan, the highest peak in Canada at 19, 551'' (5 959m), sits in the background

Valley glaciers and moraines, Kluane National Park, Yukon, Canada. Note how the lateral moraine of the smaller tributary glacier becomes a medial moraine after the two glaciers merge

Exit Glacier. Kenai Fjords National Park, SE Alaska. This glacier is fed by the Harding Icefield, seen at the high elevation

Tidewater Glacier... Marjerie Glacier.Glacier Bay National Park, Alaska

Fjord. SE Alaska

Fjord. SE Alaska

Equilibrium (Firn) line, Dinwoody Glacier, Wind River Range, Wyoming.The equilibrium line is the line between the fresh white snow above, and the gray, older ice, exposed at lower, slightly warmer elevations. The line separates the zone of accumulation from the zone of ablation on the glacier.

-shaped valley, Wind River Range, Wyoming

Valley glaciers and medial moraines, Yukon, Canada

Glacial polish and striations on granodiorite, Yosemite National Park, California.

Cirque of Grinnell Glacier, Glacier National Park, Montana. Note the glacial striations on the bedrock in the left foreground

Roche Moutonee, Yosemite National Park, California

Glacial Till, east side of Sierra Nevada Range, California

Terminal and lateral moraine at Convict Lake, Sierra Nevada, California

Glacial erratic, Newport, Rhode Island. Note how the bedrock is slate--completely unlike the granitic composition of the boulder

Retreating Glacier. Athabasca Glacier, Jasper National Park,