The Nazca and South American
Plate
The Nazca Plate is a destructive plate boundary.
A destructive plate boundary (also known as a
convergent or tensional plate boundary) is
when two plates (the oceanic and continental)
are moving towards the other. Convection
currents in the mantle move towards each
other and this enables the plates to push
against each other. The oceanic plate is
subducted under the lighter continental plate,
forming a deep trench in the sea. The oceanic
plate, then melts and because there is not
enough space for it underground, earthquakes occur. Magma then rises.
The Nazca Plate is a small oceanic plate off the coast of South America. It
produced the largest earthquake ever recorded. On May 22nd 1960, an
earthquake was 9.5 on the moment magnitude scale. A more recent even would
be on February 27th 2010, an earthquake in Chile was an 8.8 moment magnitude
earthquake. Both of these were due to the subduction of the Nazca Plate
underneath the South American Plate.
It is also one of the fastest of any tectonic plates- it moves 3.7cm east each year
and has 3 different plates come together.
Even landforms were created because of this destructive boundary. For instance,
the Andes Mountains have formed on the continental side of the subduction zone
that lies between Nazca Plate and the South American Plate. A few trenches and
some volcanos (e.g. the Cerro Azul, the Villarrica etc.) have been discovered
there, too.
The boundary is also part of The Ring of Fire (a place where many volcanos and
earthquakes are.