Plate Tectonics
Alfred Wegener and Sea-Floor Spreading
The 4 Layers
Earthquakes, Volcanoes, Mountains, Trenches, and Ridges
Plate Boundaries
100
What super continent did scientists evidence point to?
Pangaea
100
Who proposed the hypothesis of sea-floor spreading?
Herman Hess
100
What are the four layers of the Earth's interior?
crust, mantle, outer core, inner core
100
What is an example of a trench formed by a convergent-subduction boundary?
Mariana Trench
100
What are the four types of plate boundaries?
Convergent, Divergent, Transform, and Continental Rift Zone
200
Who was the scientist that came up with the drifting plates theory?
Alfred Wegener
200
How does sea-floor spreading happen?
Underwater volcanoes erupt spewing out lava which hardens, gradually moves away from the ridge, and forms new oceanic crust.
200
What layer of the Earth is the thickest and what layer is the thinnest?
The thickest is the mantle and the thinnest is the crust
200
What is an example of folded mountains?
Himalayan Mountains
200
What are the two types of convergent boundaries and what is the difference between the two?
Convergent-Subduction: the denser plate subducts under the less dense plate Convergent-Collision: two plates of the same density collide and form folded mountains
300
What plate is surrounded by over 300 volcanoes and named the Ring Of Fire?
Pacific Plate
300
What are the three evidences Wegener used to explain continental drift?
Similar fossil record found on different continents, grooves carved by glaciers were found on multiple continents, and some continents looked like they could fit together like a puzzle
300
What causes the mantle to flow?
Convection Currents
300
Where do earthquakes and volcanoes occur most?
Along the edges of plates
300
What does "divergent" mean?
Moving apart
400
How many major plates is the Earth split into?
7 to 12
400
What question was Wegener not able to answer about his theory on plate tectonics?
What kind of forces could be strong enough to move such large masses of rock over such great distances?
400
What are the two parts of the mantle?
Asthenosphere and lithosphere
400
What ridge is located along the floor of the Atlantic Ocean and part of the longest mountain range in the world?
Mid-Atlantic Ridge
400
What are two examples of divergent plate boundaries?
Mid-Atlantic Ridge and Iceland
500
What is the only state in the U.S. besides Hawaii that is not located on the North American plate and what plate is it located on?
California- located on the Pacific Plate
500
What is one thing that goes on at Mid-Ocean Ridges?
1. Sea-Floor Spreading 2. Magnetic striping 3. The youngest rocks of the sea floor are forming at the rift between the ridges
500
What part of the core is liquid and what part is solid?
The outer core is liquid and the inner core is solid
500
What is an example of a volcanic mountain chain formed by a convergent-subduction boundary?
Andes Mountains
500
What are two features of a transform-sliding boundary?
Earthquake zone or fault zone
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