Transcript Plate Tectonics

Theory of Plate Tectonics
3.1.4
4600000000 Years Old!
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Difficult to fathom as our life spans only 80
Simplified history of Earth – Waugh pg. 9
Oldest rocks are ~ 4 billion years old
Found in the Northwest Territories
•Internal
Structure of the
Earth
Crust
Sima-Oceanic
Sial-Continental
Internal Structure of the Earth
Below the Crust is the Mantle, which is relatively rigid!
Asthenosphere is part of the Mantle, that semi molten
Confused yet…
Theory of Plate Tectonics
Alfred Wegener’s 1915 drawing of Pangaea
Continental Drift
Major Plates
How do Plates Move?
What is some Evidence to
support his Theory
Good Fit
Rocks &
Mountains
Fossils
Sea Floor Spreading
Age of the Sea Floor
Evidence for the Theory
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Continental shelves seem to fit together
Rock units and mountain ranges fit Pangaea
Fossil types fit Pangaea
Ocean research uncovered sea floor spreading
Radio-geology allowed us to date the age of
rocks
6. Polarity of Rocks-Magnetic Evidence
Why do we Care?
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Curiosity
Explain landforms
Find valuable minerals
Explain and predict potential hazards
Plate Boundaries
Where the Action Is
• Where new land is created
• Where most the most interesting landforms
are found
• Where most Earthquakes & Volcanoes
occur
Earth Quakes and Volcanoes
What Happens at Plate
Boundaries?
Subduction Boundary
Ocean to Ocean
Satsuma Iwojima – Cinder Cone Volcano, Japan
Subduction Boundary
Ocean to Continent
Mt. Rainer, Washington State
Subduction Boundary
Continent to Continent
Sagarmatha - Himalayas
Divergent Boundary
Ocean Ridges
East African
Rift Valley
Collision Boundary
Eastern Sierra
Fold Mountains
Transform Boundary
San Andreas Fault - California
Hot Spots
Haleakula Crater, Maui
Hot Spot Volcano