Subduction Flashcards
1
Q
Evidence?
A
The trench Fold mountain belts- eg Andes Seismic activity Explosive volcanic activity Age of ocean lithosphere Ophiolote suites
2
Q
How does seismic activity show evidence?
A
As the crust travels through the mantle it causes earthquakes, as you go inland the focus gets deeper cause the crust goes through at an angle
3
Q
How does explosive volcanic activity show evidence?
A
When basalt is created it comes up through the mantle and changes to form andesite which is explosive, it changes due to mixing with granitic continental
4
Q
How does the Age of the ocean lithosphere show evidence?
A
Oldest ocean lithosphere-200 mya
Oldest continental-3900 mya
Must be being destroyed
5
Q
What is subduction?
A
Oceanic lithosphere subduction underneath the continental
