Location
and tectonic setting
Cotopaxi is a glacial
volcano located about 35 miles south-southeast of Quito,
Ecuador.15, 13 For a time, it was
considered the highest active volcano in the world, at
5911 meters elevation, or 19,393 feet.2 It is
a subduction zone volcano and part of Ecuador's eastern
volcanic row, and it has most recently been erupting
only andesitic lava, although it has erupted rhyolitic
lava in the past.13 It is a stratovolcano, and
one of the few glacial volcanoes near the equator.13
It is also part of what is commonly referred to as the
Ring of Fire, the chain of subduction zone volcanoes
that surrounds the Pacific Ocean.
Latitude: 0.677°S
0°40'38"S
Longitude: 78.436°W 78°26'10"W 2
Map of Ecuador16
The Volcanic Arc in Ecuador
Cotopaxi as part of the highlands
of Ecuador. Other volcanoes within the region include
the currently erupting Guagua Pichincha and Tungurahua.17
Subduction zone volcanism:
Subduction zone volcanism
occurs when an oceanic plate is pushed under a
continental crust; as the oceanic plate, mixed with
water and sediment, descends into the earth, it melts
and becomes magma, which rises through the continental
crust and is erupted, usually explosively, through
volcanoes, as seen below. To see a video of this
process, visit:
http://www.classzone.com/books/earth_science/terc/content/visualizations/es0902/es0902page01.cfm
This image was taken from the
PowerPoint slides of the infamous Karen Harpp of Colgate
University.20 Infamous.
Cotopaxi is one of the
many volcanoes in South America that is the result of
the Nazca oceanic plate subducting under the South
American Plate.24
The earth's tectonic movement22
The Pacific Ring of Fire21
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