Is THINNER (7km) but DENSER than the
Continental Crust and therefore SINKS
Is YOUNGER than Continental Crust
Oceanic Crust is continually
being FORMED and DESTROYED
e.g. Pacific Plate
the Mantle is Layers of Molten Rock and the widest
section of the Earth
the Inner Core is The very hot
centre of the Earth
the Outer Core is The liquid layer surrounding the inner core,
which is also made up of iron and nickel
Plates: Huge Scabs of the Crust
Plate Boundary: The place where
two plates meet
Pangae
Around 200 million years ago the
continents were joined together to form a
Super Continent called Pangae
Pangae began breaking up and since
then the continents have been drifting
away (Continental Drift)
Evidence
Shapes of the continects today look as though
they fit together E.g. South America and Africa
There are similar patterns of rocks/plants and similar
fossils found have been found in both continents
Plates
7 major plates and many smaller ones
North American plate
South American plate
Eurasian plate
African plate
Indo-Australian plate
Pacific plate
Nazca plate
Destructive Plate Boundaries
At an destructive plate boundary the plates are
moving together. The denser oceanic crust sinks
into the mantle where it melts in the subduction
zone. the nergy may be released as an earthquake
and the molten magma may rise upwards causing
a volcanic eruptiion. The continental crust becomes
crumpled into fold mountains.
Constructive Plate Boundaries
At a Constructive Plate Boundary the
Plates are moving apart. This type of
movement mostly happens under the
oceans. The gap left is filled with magma
rising up from the mantle below the
volcanoes. Some of these volcanoes have
become large enough to form volcanic
islands such as iceland and Hawaii.
Conservative Plate Boundaries
The plates are moving past each other either
in the same or opposite directions. They are
sometimes called passive margins. The two plates
meet at a fault and the pressure builds up until the
two plates jerk past each other. This can cause an
earthquake and the land at the fault becomes
crumpled and rigid. A good example is the San
Andreas fault in California.