Answer 1:
There are on Earth about 12 or so of these
plates. The continents ride on these plates, hence
the continents change latitude and longitude
because they are carried by the spherical caps or
plates.
There are three types of plate boundaries: type
one is where two plates are diverging. This
means that stuff from BELOW the plates rushes up
to fill the opening. This occurs along ocean
ridges. There are about 7, 0000 km (linear), or
43,496 miles of diverging plate boundary.
Then type 2 plate boundaries: converging
plates. When this happens one plate dives
beneath the other. If the plate diving beneath the
other has a continent on it, then the continent
will make the process stop when the continent is
moved to the region where subduction is taking
place.
Finally type 3 plate boundaries: two plates
slide past each other such as along the San
Andreas Fault where we live.
Because the motion of the plates is irregular,
it is indeed possible for two plates each of which
has a continent piggy backing on to collide. When
these two plates undergo subduction, then the two
continental blocks will be slammed into each other
and a high mountain range will form. This is
happening TODAY to produce the Himalaya Mountains,
because INDIA used to be attached to AFRICA, and
in the past 70 million years it has moved north
and is now slamming into ASIA/CHINA.
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