The surface of the Earth is divided into a number of large 'slabs' of rock called tectonic plates. The divisions between these are shown in the
map. These plates are not stationary but are moving very very slowly across the
surface of the planet. In some places they are sliding past each other, in some places
they are colliding and in others they are moving apart. This movement is known as
continental drift. The movement of the Indo
Australian plate towards the Eurasian plate caused the formation of the
Himalayas.
The places where the plates meet are regions of high volcanic activity
and where the danger of earthquakes is high. Notice the San Andreas Fault in California and
the origin of the 2005 tsunami in Indonesia lie along the meeting point of two tectonic
plates.