Plate tectonics Flashcards
After midterm 1
Which is more dense, a continental plate or oceanic plate
Oceanic plate is more dense - 3.0g/cm^3
Continental plate is less dense - 2.7g/cm^3
Oceanic plates are composed of what type of rock
Basaltic rock
Continental plates are composed of what type of rock
silica rich
At what rate do lithospheric plates move
cm/year
What are the 3 types of lithospheric plate boundaries
Divergent, convergent, transform
Are divergent boundaries tension or compression
Tension
Do divergent boundaries create r destroy crust
they’re constructive, so they create crust
in divergent boundaries, new lithosphere can be created by what
volcanism
What is an example of a divergent plate boundary rift valley
east-African rift valley
Divergent plate boundaries typically create continental or oceanic crust
oceanic crust
The mid-Atlantic ridge is what type of boundary
ocean-ocean divergent
Why is there a lot of volcanic activity in Iceland
the mid-Atlantic ridge passes through it
What kind of deposits do we find at divergent plate boundaries
metal deposits
Is convergent plate boundaries compression or tension
Compressions, they’re in collision
Convergent:
the_______ plate is forced beneath the other and down into
the mantle, this process is known as subduction
denser