AGENTES GEOL

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The geological action of water II(La acción
geológica del agua)
Water shape the Earths surface through its
movements in surface runoff, rivers, seas,
glaciers and underwater stream.- Surface runoff
or wild waters (Aguas de arroyada o aguas
salvajes )- Rivers (ríos)- Glaciers
(glaciales)- Sea (el mar)
2
The parts of an alpine glacier An alpine glacier
is a glacier formed on mountainsides and moves
downward through valleys.
3
Glaciers (glaciares)glaciers are large masses of
ice in movement, descending valleys from higher
zones until they reach levels where they begin to
thaw.
The glacial erosion is due to friction of the
rocks transported by ice against rock.
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Striations (estrías) the hardest pieces of rock
carried by the ice scratch (friction) the sides
of the valley causing striations.
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CIRQUE GLACIER (Circo de un glaciar)

• A cirque is a depression surrounded by mountains
  where the snow accumulates and through
  compression it becomes ice.

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Tongue Cirque (accumulation zone)

• The mass of ice wich slides down the valley is
  the tongue (lengua de un glaciar).

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Tongues Cirques
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MORAINES (morrenas)The accumulation of rock
fragments are called moraines, these fragments
are transported and deposited by the action of
the glacier.Depending on their position, these
are classified as lateral, medial, ground and
terminal moraines (morrenas laterales, centrales,
de fondo y frontales, respectivamente).
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• Terminal moraines

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Medial moraines
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U-Shaped Valley Glaciers form a characteristic
valley with the shape of a U.
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U-Shaped Valley
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What parts of an alpine glacier can you
distinguish in the picture on the left side?
What has been happening in the picture to the
right?