What are the two types of continental margin?

Question 1

What are the two types of continental margins?

Answer 1

Passive and Active

Question 2

Which is more common?

Answer 2

Passive continental margins are more common, especially along the east coast of the Americas, the west coast of Europe and around Africa, India, Australia and Russia * Active continental margins are also common, especially along the northern and eastern margin of the Pacific plate and in southeast Asia

Question 3

Where does most subduction occur?

Answer 3

Most subduction occurs around the Pacific plate, in south-east Asia and at the Caribbean and Scotia plates
Most subduction is oceanic-continental although sometimes it is a bit mixed

Question 4

Where does oceanic-oceanic subduction occur?

Answer 4

Oceanic-oceanic subduction occurs mostly along the mid and southwestern margin of the Pacific plate, and at the Caribbean and Scotia plate (true oceanic-oceanic subduction)

Question 5

What are convergent plate margins interrupted by?

Answer 5

Convergent plate margins are regularly interrupted by transform faults

Question 6

What factors cause an oceanic plate to subduct under another oceanic plate?

Answer 6

Overall, the older lithosphere will conduct underneath the younger lithosphere as it has more time to cool down and will have sunk down due to isostasy (sit lower in elevation due to isostasy and it is denser as it has had more time to cool)
There are other factors that may play a role in the different regional settings, such as history of subduction, isostatic state, geometry of the margin, mechanical state of the two plates, properties of the upper mantle etc