South
American plate
African
plate
Scotia
plate
North American
plate
Eurasian plate
North American
plate
Pacific
plate
Juan de Fuca
plate
Cocos
plate
Nazca
plate
Pacific plate
Antarctic plate
Indo-Australian
plate
Philippine
plate
Caribbean
plate
Anatolian
plate
Iranian
plate
Arabian
plate
volcano
plate movement
8 000 km
0
1:335 000 000
N
2
30
2. Relief
2. HOW RELIEF IS BUILT
The great landforms of the Earth’s relief, including those on emerged land (continents)
and on submerged land (ocean floors), are the result of the forces of enormous
pressure from the Earth’s interior, called
orogeny
(from the Greek
oro
, meaning
‘mountain’ and
genesis
, meaning ‘creation’).
2.1. Tectonic plates and their movements
The tectonic plates lie on top of the
mantle
, which is in a
semi-solid
state.
The tectonic plates move over the mantle slowly and continually, over millions of
years. During this movement, plates collide and separate.
Tectonic plates and main volcanic zones
The crust and the upper part of the mantle constitute the
lithosphere
. It is divided
into a series of
large blocks
, the
tectonic plates
. These plates make up a giant
puzzle whose pieces are the
continents
and
ocean floor
.
!
Important
When the plates move, they
interact in three basic ways:
They collide with each other.
They separate from each other.
They slide past each other.
The
Earth’s crust
is not smooth
2
. There are
plains
,
valleys
,
depressions
and
mountains. All these geographical features together are called
relief
.
2
smooth
:
flat, without projections
3
buckle
:
to bend
