1. Plate Tectonic Makeup Bellwork

2. Bellwork
Alfred Wegener could not explain what caused the continents to move. It is now believed that _____ currents inside Earth cause plates to move.
Bands or stripes of basaltic rock on the seafloor showing alternating magnetic orientation indicate Earth's magnetic field has _____ in the past.
While studying the ocean floor, scientists found _____ of magnetism.
As you get farther from a mid-ocean ridge, sea floor rocks become _____.
Answer Bank
convection
Mid-ocean ridges
older
stripes
reversed

3. Bellwork
Answer Bank
older
Ocean ridges
Continental
Fossils
seafloor
(see figure above) As you get farther from a mid-ocean ridge, sea floor rocks become ______.
Alfred Wegner noticed that the _____, rocks, and mountains matched up across continents
Mid-_____ _______ are a continuous chain of volcanoes that extends through many of the earth’s oceans where new crust of the Earth is created.
The two theories that lead up to plate tectonics are ______ drift and ______ spreading.

4. Bellwork 1. Earth’s magnetic field protects us from the ____ ______
2. When magma cools at mid-ocean ridges, a mineral called magnetite ______ itself with the earth’s magnetic field.
3. Harry Hess noticed ______ on the seafloor.
4. Each magnetic ________on the seafloor showed a _______in the earth’s magnetic field.
5. These magnetic stripes were strong evidence for seafloor ________ and plate tectonics.
Answer Bank
Reversal
Reversed
spreading
Stripe(2)
younger
Solar wind
aligns

5. Continental (use twice)
Bellwork
East Africa and Mid-ocean ridges are two examples of a _______ plate boundary.
A _______ zone is the area where the plate sinks back into earth melting as it descends.
The two types of crust are ________ and _______ crust.
An island arc like Japan formed by a collision of ocean crust colliding with _____ crust at a convergent plate boundary.
The Himalayan Mountains formed from the collision of continental crust colliding with _________ crust.
6) Draw
& Label:
Answer Bank
Subduction
Continental (use twice)
Ocean (use twice)
Divergent
Rift Valley
Convergent Boundary
Divergent Boundary
Subduction Zone

6. Bellwork
A _______ is located at location A where plates collide and ocean plate subducts .
2) New rock or plate is created at ______ boundaries and plate is destroyed at _________ boundaries.
3) At location B, ocean plate is _____ as it subducts and sinks
4) The subduction of oceanic plate beneath continental plate produces ____ _____
Answer Bank
Volcanic mountains
Trench
convergent
Divergent
Melting