Thursday, February 10, 2011

The Amazon Landscape

The Amazon River once flowed westward into the Pacific Ocean about 15 million years ago.  After that, the South American Plate moved into the Nazca Plate creating the Andes Mountain.  Because the mountains interfered with the flow of the river, it backed up and eventually formed fresh water lakes creating a new environment.  The river later found its path eastward into the Atlantic Ocean
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 Victoria Falls

The Amazon Basin is made up of sedimentary layers of soft clay that is extremely thick. Andesite rocks are igneous, volcanic rocks that are most commonly founded in the Andes Mountains.  Due to the enriched soil of the tropical rain forest, numerous of minerals are founded in the rain forest.  The most common minerals are magnetite, zircon, apatite, ilmenite, biotite, and garnet.


Sample of andesite
The Andes  Mountains is located in an area where continental-oceanic collision occurs thus causing explosive volcanism.  The process of intrusive landforms results from magma solidifying beneath the earth's crust which is later uplifted and exposed by erosion.  Earthquakes, glacial activity, and erosion later on brings the magma to the surface. 
   Volcanic Landforms in the Andes Mountains
The Andes Mountains are formed on the west coast of South America during the end of the Mesozoic Era by the process of two major colliding tectonic plates. The lighter Nazca plate in the Pacific Ocean converged under the heavier American Plate; also known as Subduction.

Andes Mountains

References for text:
http://science.jrank.org/pages/6300/South-America-Andes.html
http://www.worldatlas.com/webimage/countrys/saland.htm
References for images:
http://www.monnikhof.com/Victoria-Falls-2.jpg
http://cdn.wn.com/pd/a0/72/88e23b1ceffa304131933e080fe6_grande.jpg
http://adv-model-earth-syst-discuss.org/meetings/fm09/program/images/V23D-2099_A.jpg
http://www.treehugger.com/andes-mountains-peru.jpg