Plates that undergo tension (stretching) stress are found at what type of boundary?
divergent
100
Approximately how many major plates make up the majority of the Earth's lithosphere?
6-7
100
What was the super continent called that existed approximately 245 million years ago?
Pangaea
100
Which plate goes underneath during convergent subduction boundaries?
the less dense oceanic crust
100
Which plates move away from each other?
divergent plates
200
Plates that undergo compression (squeezing) stress are found at what type of boundaries?
Convergent
200
Which layer of the Earth is all liquid and made primarily of iron?
outer core
200
What was Alfred Wegner's theory called?
theory of continental drift
200
Which plate boundary has the most earthquake activity?
transform boundaries
200
Who came up with the theory of continental drift and when?
Alfred Wegner, 1912, not accepted by public until the 1960's
300
Plates that undergo shearing (pushing in opposite directions) stress are found at what type of boundaries?
transform
300
A sudden release of energy in the Earth's crust that creates seismic waves is known as ___________________.
earthquakes
300
What layer of the Earth is divided into tectonic plates?
lithosphere
300
Which plate boundary creates new crust?
divergent boundaries
300
Which plate boundary, that undergoes shearing stress, also has strike slip faults?
transform boundaries
400
What are the 2 types of convergent boundaries?
convergent collision and convergent subduction
400
Fractures in rocks where movement occurs are called _____________.
faults
400
What causes tectonic plates to move?
convection currents (heat currents)
400
Which plate boundaries are most likely to form volcanoes?
convergent subduction
400
According to the theory of continental drift...what will happen to the USA in the next 300 million years?
the west coast will "break off" due to moving plates
500
What is the difference between convergent collision and convergent subduction?
convergent collison (land plate and land plate) both go up and form mountains... convergent subduction (land plate and oceanic plate) on plate goes under the other plate
500
What are the 3 types of evidence Alfred Wegner used to support his thoery of continetnal drift.
fossils
rocks
glacier grooves
500
What is the layer called that the lithosphere "floats" on top of?
aesthenosphere
500
Which plate boundary is most likely to form folded mountains?
convergent collision
500
True or false....temperature and pressure increase towards the center of the Earth?