Crust Flashcards
1
Q
How thick is oceanic crust?
A
6-7km with 4.5km elevation
2
Q
What is the density of oceanic crust?
A
2.9gcm-3
3
Q
Where is oceanic crust former?
A
MOR
4
Q
What is the composition of oceanic crust?
A
Basaltic with high Mg/Fe, low Si
5
Q
How thick is continental crust?
A
35-40km thick with 1km elevation
6
Q
What is the density of continental crust?
A
2.7gcm-3
7
Q
What is the composition of continental crust?
A
Granitic, with High Si/Na/K and low Mg/Fe
8
Q
What does adiabatic up welling produce?
A
Pikritic basalts that rise through mantle and accumulate in magma chambers
9
Q
What mineral crystallises first?
A
Olivine crystallises and fractions first with MORB @ 8-10% MgO and 50% SiO2
