By the way, if you haven't noticed, this is about Glacier Bay National Park, in Alaska....one of my many school assignments! =)~If you are a student and have a webpage of your own, or you know someone else who has a really cool page, please e-mail me, because I could always use new information.
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Glacier Bay National Park and Preserve is made up of a biome called a tundra. Tundras are arctic plains encompassing most of the earth's northern terrain. Tundras can be found in Europe, Antarctica, and North America. Glacier Bay National Park is located in Alaska. If you would like to contact them, their address is:
Glacier Bay National Park and Preserve
P.O. Box 140
Gustavus, Alaska 99826
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Glacier Bay Geology Report:
Explorer George Vancouver found Icy Strait choked with ice in 1794, and Glacier Bay was barely an indented glacier. That glaier was more than 4,000 feet thick, up to 20 miles or wider, and extended more than 100 miles to the St. Elias Range of mountains. But by 1879 naturalist John Muir found that the ice had retreated 48 miles up the bay. by 1916 the Grand Pacific Glacier headed Tarr Inlet 65 miles from Glacier Bays' mouth. Such rapid retreat is known no where else. Glaciers form because snow fall in the high mountains exceeds snowmelt. The snowflakes first change to granular snow-round ice grains-but the accumulating weight soon presses it into solid ice. Eventually, gravity sets the ice mass flowing downslope at 7 feet per day. The park includes some 12 tidewater glaciers that clave into the bay. As water undermines some ice fronts great blocks of ice up to 200 feet high breakloose and crash into the water. The glaciers seen there today are remanents of a general ice advance-the Little Ice Age-that began 4,00 years ago. The Little Ice Age reached its maximum extent here about 1750,when general melting began. Today's advance or retreat of a glacial snout reflects many factors: snowfall rate, topography, and climate trends. Glacial retreat continues today on the bays' east and southwest sides, but on its west side two glaciers are advancing. The snow-capped Fairweather Range supplies ice to all glaciers on the peninsula separating Glacier Bay from the Gulf of Alaska. Mount Fairweather, the ranges highest peak, stands at 15,320 feet. Near John Hopkins Inlet, several peaks rise from the sea level to 6,520 feet within just 4 miles of shore. The great glaciers of the past carved these fjords, or drowned valleys, out of the mountains like great troughs. Landslides help widen the troughs as the glaciers remove the bedrock support on upper slopes. Colors betray a bergs' nature or origin. White bergs hold many air bubbles. Blue bergs are dense. Greenish-blackish bergs have calved off glacier bottoms. Dark-striped brown bergs carry rubble. How high a berg floats depends on its size, the ice's density, and the waters' density. The park contains many kinds of rocks/ Clastic, carbonate, volcanic, metamorphic, gneiss, foliated granite, unfoliated granite, gabbroic, and newly deposited sedimentary rocks. Most of Glacier Bay is composed of clastic rock and foliated granite rock, with rarely any metamorphic rocks. That is the geology of Glacier Bay National Park.
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