Plate Boundaries
Which boundary type can result in mountains and trenches?
Convergent
Volcanoes can be found in which TWO plate boundary types?
Convergent and Divergent
Evidence of Continental Drift
Fossils, climate, rocks, glacial deposits
The oldest rock in the seafloor is found where?
Near the trenches/in the subduction zone.
Alfred Wegener
Proposed the continental drift theory in the 1900s
Describe a Transform Boundary
The boundary between tectonic plates that are sliding past each other horizontally
Describe a Convergent Boundary
The boundary formed by the collision of two plates moving toward each other
What is Continental Drift?
The hypothesis that says that the continents once formed a single landmass, broke up, and drifted to their present locations
What causes older rock towards the trenches?
The magma wells up and pushes the rock
What is convection current?
The movement of rock/magma in the mantle.
What is Sea-floor spreading?
The process by which new oceanic crust forms as magma rises towards the surface and solidifies
What is the Asthenosphere
The soft layer of the mantle on which the tectonic plates move
What is the Lithosphere
The solid, outer layer of the Earth that consists of the the crust and the rigid upper part of the mantle
Plate Tectonics
The theory that the earth is broken into plates and are in motion due to convection currents in the asthenosphere (upper mantle)
Crust
The thin and solid outermost layer of the Earth above the mantle
During convection in the TOP of the lower mantle, rock (heats up / cools down).
cools down
Which boundary type can create rifts and ridges?
divergent
What is the only thing that Transforming plate boundaries will create?
earthquake
What can happen at all types of plate boundaries? (earthquakes, volcanoes, trenches)
earthquakes
Which of these formations (1) can occur at a TRANSFORM boundary? (mountain, volcano, earthquake, ridge, rift, trench)
earthquakes
What is a trench?
extremely deep areas in the ocean that are created by a subducting plate
During convection in the TOP of the lower mantle, rock (rises / falls).
falls
During convection in the BOTTOM of the lower mantle, rock (heats up / cools down).
heats up
During convection in the BOTTOM of the lower mantle, rock becomes (more / less) dense.
less - this is why it will then rise
What is a rift?
long, narrow depression formed at divergent boundaries
How is new seafloor material in Earth's crust formed?
magma rises to fill spaces where plates have pulled away from one another
During convection in the TOP of the lower mantle, rock becomes (more / less) dense.
more - this is why it begins to then sink
All of these formations can occur at a DIVERGENT boundary EXCEPT _________ and _________. (mountain, volcano, earthquake, ridge, rift, trench)
mountains and trenches
Direction of movement for a DIVERGENT boundary: (toward / away / slide past)
moves AWAY from each other
Direction of movement for a CONVERGENT boundary: (toward / away / slide past)
moves TOWARD each other
All of these formations can occur at a CONVERGENT boundary EXCEPT _________ and _________. (mountain, volcano, earthquake, ridge, rift, trench)
ridges and rifts
During convection in the BOTTOM of the lower mantle, rock (rises / falls).
rises
How is seafloor material destroyed or "recycled"?
rock material is subducted (sinks) into trenches
Direction of movement for a TRANSFORM boundary: (toward / away / slides)
slide past each other
Pangaea or Pangea
term for the super continent which contained all the plates together
Rocks found on opposite sides of the Mid-Atlantic Ridge prove the theory of Plate Tectonics because they are (older / newer).
the rocks farther and farther from the ridge are older
Where would you find the newest seafloor rock in the ocean?
the top of the ridge
What is subduction?
two plates collide and the denser ocean plate descends below the other
Describe a Divergent Boundary
two tectonic plates that are moving away from each other
