Boundaries
What is a convergent boundary?
where two plates collide.
What is the Theory of Plate tectonics?
describes large-scale movements of Earth’s lithosphere, which is made up of the crust and the rigid, upper part of the mantle.
What did Alfred Wegener propose?
Continental drift
What are the most common geologic events around ridges?
volcanic activity and earthquakes
What is a divergent boundary?
Where two plates move away.
What are tectonic plates?
The lithosphere is divided into pieces called tectonic plates.
What theory replace continental drift?
The theory of plate tectonics
Where do most volcanoes and earthquakes take place?
at plate boundaries
What is a transform boundary?
where two plates move past each other.
What 3 mechanisms cause the plates to move?
mantle convection, ridge push, slab pull.
What is continental drift?
the continents were once all joined together (pangaea) and have drifted apart over time/
Volcanoes are created by what 2 boundaries?
divergent and convergent
What is created by a transform boundary?
Earthquakes
When the continents were joined together what were they called?
Pangaea
Did everyone believe Alfred Wegener at first?
No
Earthquakes are created by what type of boundary?
transform
What is created by a divergent boundary?
mid-ocean ridge
What is the process where molten rock from inside Earth rises through the cracks in the ridges, cools and forms new oceanic crust?
Seafloor spreading
Complete the following sentence:
Earth’s crustal plates are _______ and were once a _______ called Pangea.
Earth’s crustal plates are moving and were once a supercontinent called Pangea.
What is a subduction zone?
where rock is recycled by one plate sliding underneath another tectonic plate.