Gcse AQA Geography Volcano and Earthquakes

STRUCTURE OF THE EARTH

The Earth is made up of 4 main parts: starting from the outside

• Crust
• Mantle
• Outer Core
• Inner Core

There are two types of plates that move around our earth by Convection Currents in the Mantle... these are the Oceanic and Continental Plates. The Oceanic Plates are made from denser rock that continental Plates.

FOLD MOUNTAINS

Fold mountains are formed where two plates converge. The rocks in the crust are compressed, folded and faulted to form new mountain ranges. Areas of fold mountains include the Alps, Andes, Rockies and Himalayas.

PLATE BOUNDARIES

TENSIONAL BOUNDARIES - CONSTRUCTIVE

• Oceanic OR Continental plates diverge (Move Away)
• Mantle rock melts and erupts as lava
• New crust is formed
• Undersea Volcanoes form mid ocean ridges
• Minor earthquakes occur as the plates move.

COMPRESSIONAL BOUNDARY - COLLISION

• Continental plates converge
• Plates are not dense enough to sink into the mantle
• Plates buckle and form fold mountains
• There are powerful earthquakes, but no volcanic eruptions

COMPRESSIONAL BOUNDARY - DESTRUCTIVE

• Oceanic and continental plate converge
• Denser oceanic crust is forced…