Constructive Landforms

Question 1

What are the three landforms associated?

Answer 1

Oceanic ridges
Transform Faults
Rift Valleys
Volcanoes

Question 2

Characteristics of ocean ridges are?

Answer 2

1. combined length of 60,000 km
2. may feature a central valley.
3. youngest part of the ocean.
4. can reach 1 km in height.
5. for example Mid-Atlantic Ridge

Question 3

How are ocean ridges formed?

Answer 3

1. as plates pull apart, magma rises to surface as there is lower pressure.
2. the magma cools down and solidifies.
3. the hot crust expands to form a ridge.
4. rough topography is formed, rifts and scarps.

Question 4

What are transform faults?

Answer 4

1. they bisect the main ridge and are offset from the main ridge.
2. they move out at different rates.
3. created by crustal uplift and tectonization.
4. shallow focus earthquakes occur

Question 5

Characteristics of rift valleys are?

Answer 5

1. formed on continental/continental margins
2. characterised by dropped down and uplifted sections of rocks, horsts and grabens.
3. may have active volcanoes to evidence igneous activity.
4. steep valley sides.

Question 6

How are rift valleys formed?

Answer 6

1. spreading occurs, crust heats up and domes.
2. the rocks crack and break up
3. central sections drop down to form rift valleys.
4. for example the Great African Rift Valley, with Mount Kilimanjaro and Lake Victoria in valley.

Question 7

How volcanoes form..

Answer 7

plates pull apart and magma rises to erupt on surface to form volcanoes land and submarine.
islands can form as they reach surface, e.g. Iceland, recently Surtsey.