By Noah Bell
Scientists discovered that the
continents that make up the land on earth, were once all conjoined in one land
mass called Pangaea. This would only mean one thing; the continents had to have
moved away to become the land we know today. The Earth’s crust is made up of
different plates that “float” on the mantle. There are three different kinds of
boundaries where these plates meet; divergent boundary, transform boundary, and
convergent boundary. Divergent boundaries are when two plates are moving away
from each other. This allows magma to flow up in between the two plates,
forming new crust. Transform boundaries are where two plates are moving two
different ways and grinding against each other. This creates vibrations, or as
we know them, earthquakes. Convergent boundaries are where two plates are
moving towards each other and smash together. This could either cause mountains
to form or one of the plates could submerge under the other and be recycled. When
a plate is recycled, it creates less dense magma that floats up to the crust
and is released through volcanoes.
Recently, Scientist are discovering
that a section of a plate has actually been missing. The Isabella anomaly is a section
of the Farallon plate that has submerged underneath the North American plate.
Usually when plates submerge under one another, they are recycled and transformed
into new magma. This is an unusual case where the Isabella anomaly submerged user
the North American plate, but was not destroyed. Instead it was pinned against
the underside of the North American plate. This is supporting evidence that we
do not know everything about plate tectonics and are learning more every day.
Big Boom, this is a solid post with decent explanations. I think it could be enhanced with some pictures (illustrations or actual photographs) to show exactly what's happening, but maybe in the next post. Keep up the good work.
ReplyDelete- iandwest