AS 90935

Key surface features:• High mountain ranges (1st)• U-shaped valleys (2nd)

Internal processes:• Convection currents move the plates• Both plates colliding (destructive

plate boundary) leading to uplift

External processes:• Glaciers acting as a weathering and

erosion agent• Rise and fall of sea level

• Three processes must be linked to the surface features for E. At least one internal and one external process is needed (last one can be either).

• One of each must be linked for M. • All info must be in the context

Step one

Find/draw a diagram (cross section) to show the three ideas:• Surface features • Internal processes• External processes Annotate this diagram (around the diagram or refer to in the report).

Step two

• A description of the surface features:• Mountain ranges• U-shaped valleys

Step three

Explain the first internal process that has caused the mountain ranges to form.• Convection currents (explain how they occur)• Name the two plates that the sounds are found on• Link the direction of the current to how the plates

are moving • What type of plate boundaries has this caused?• When was this happening? (most recently)

Step four

Explain the second internal process that has caused the mountain ranges to form.• What type of plate boundary has this caused?• When was this happening? (most recently) • Where has uplift occurred What type of rocks

were being exposed (age type?)• CONTEXT, CONTEXT – LINK TO THE SURFACE

FEATURES

Step 5 Explain the first external process that has caused the U-shaped valleys to form.• Ice ages and interglacial periods• Cooler periods cause ice to accumulate in the crevices

between the mountains (forming glaciers)• Warmer periods cause the glaciers to move down the

mountain • During this process large rocks are weathered and eroded

away• Detail into the weathering and erosion • Retreating of the glaciers leaving behind the valley

Step 6

Explain the second external process that has caused the U-shaped valleys to form.• The glaciers retreated (due to periods of

warming)• Sea level rises • Bottom of the valley is filled by water