Page 362 - Laboratory Manual in Physical Geology

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FIGURE 13.2 Mountain glaciation. This is an ASTER infrared satellite image of a 20-by-20 km area in Alaska. Vegetation appears red,

glacial ice is blue, and snow is white. (Image courtesy of NASA/GSFC/METI/ERSDAC/JAROS and U.S./Japan ASTER Science Team.)
There are five main kinds of glaciers based on their ■ Ice sheet —a vast, pancake-shaped ice mound that
size and form. covers a large portion of a continent and flows
independent of the topographic features beneath it
■ Cirque glaciers —small, semicircular to triangular and covers an area greater than 50,000 km . The
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glaciers that form on the sides of mountains. If Antarctic Ice Sheet (covering the entire continent of
they form at the head (up-hill end) of a valley and Antarctica) and the Greenland Ice Sheet (covering
grow large enough, then they evolve into valley Greenland) are modern examples.
glaciers.
■ Ice cap —a dome-shaped mass of ice and snow that
■ Valley glaciers —long glaciers that originate at cirques covers a flat plateau, island, or peaks at the summit of
and flow down stream valleys in the mountains.
a mountain range and flows outward in all directions
■ Piedmont glaciers —mergers of two or more valley from the thickest part of the cap. It is much smaller
glaciers at the foot (break in slope) of a mountain range. than an ice sheet.
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