4.1 Crash Course - Plate Tectonics

Which  of the following were used as evidence for Pangea ?  Select all that apply.  (feel free to go back and watch again, she said them fast)

• Spatial distribution of fossils (same fossils found on different continents)

• Location of rock types & Mountain ranges (same rocks & mountains found across continents)

Where is new oceanic crust formed?

• At the mid-ocean ridge from new magma coming up. 

• By continents sinking. 

What happened to the old oceanic crust when it came into contact with a continental plate?

• It was subducted, pulled down into the mantle

• It formed mountain ranges

At a subduction zone...

• Dense continental crust is subducted under lighter oceanic crust.

• Dense oceanic crust is subducted under lighter continental crust.

Which of these is INCORRECTLY matched?

• Transform boundaries = plates move sideways with no friction. 

• Divergent plate boundaries = plates moving away from each other, magma wells up, sea floor spreads. 

• Convergent plate boundaries = one plate is dragged under another, turning the subducting plate under and melting it. 

• Continental plates colliding = convergent, mountain building. 

Why might plate tectonics have fueled the diversification of life?

• By supplying nutrients

• By creating volcanoes