Download hotspots and magnetic reversals

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hotspots and magnetic
reversals
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Pacific Ring of Fire
Volcanism is
mostly focused
at plate margins
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Volcanoes are formed by:
- Subduction - Rift valleys - Hotspots
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subduction and collisions
Subduction - When one crust sinks
below another crust and melts,
allowing magma to rise at the
surface.
Collisions – when mountians form
when two plates collide into each
other
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Pacific Ring of Fire
Hotspot
volcanoes
+ What
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are Hotspot Volcanoes?
*A hotspot is a location on the Earth's
surface that has experienced active
volcanism for a long period of time.
*Hot
mantle plumes are areas where
magma collects and rises from the mantle
to the surface inside tectonic plates.
The Hawaiian island chain are
examples of hotspot volcanoes.
+ *The tectonic plate moves over a fixed
hotspot forming a chain of volcanoes.
The youngest volcanoes are located on
top of the hot spot and get older, the
further out they are.
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Magnetic Reversals Videos
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https://youtu.be/Ou1BiorYRNU
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https://youtu.be/igGsuDYxhEA
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Magnetic Reversals
Magnetic Reversal*
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*Magnetic reversals are found in volcanic rock on the
sea floor on either side of the mid ocean ridge.
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*As the magma on the sea floor cools and hardens, it
aligns in a pattern of magnetized stripes which holds
records of reversals in the Earths magnetic field.
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*The youngest rock records are located the closest to
the mid ocean ridge
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