plate boundaries

Question 1

what are the 5 pieces of evidence for plate tectonics ?

Answer 1

1. jig saw fit (self explanatory)
2. fossil evidence
3. palaeomagnetism
4. geology
5. climatology

Question 2

What is climatology ?

Answer 2

This is the study of the past climates that proves tectonics for example Newcastle used to be tropical therefore having now large reserves of coal.

Question 3

What are some examples of fossil evidence ?

Answer 3

This is the Mesosaurus that was a fresh water lizard - fossils where found in the south west of Africa and on south America it couldn’t have travelled over the sea as it is salt water.

Question 4

What is geology and how can it be used to prove plate tectonics ?

Answer 4

This is the study of rocks and can be used as Canada’s rocks are the same as the ones found in Scotland.

Question 5

what is palaeomagnetism ?

Answer 5

This the idea that at constructive or divergent plate boundaries the magma that creates the new land has a polarity over the space of 200,000 - 400,000 years the polarity will change meaning the polarity of the rising magma will too. This creates magnetic stripping.

Question 6

What are the 3 types of lava ?

Answer 6

1. rhyolitic
2. andesitic
3. basaltic

Question 7

What are the viscosities of all 3 of the lavas ?

Answer 7

1. rhyolitic is very viscous because of its high silica content
2. andesitic is a median between the 2 spectrums of lava
3. basaltic is a low viscosity and is fast flowing as it is often found far from destructive plate boundaries so low silica content.

Question 8

What is slab pull ?

Answer 8

This is when denser oceanic plates are subducted as it sinks into the mantle it pills the plate downwards.