arth’s Structur d Plate Tectoni
Jan 03, 2016
Earth’s Structure and Plate Tectonics
•Core- center of the earth, made up of iron and nickelOuter core is liquid and inner core is solid
•Mantle- several layers, contains most of the earth’s mass,
•Magma- molten rock, forms in the mantle
•Crust- thin layer of rock at the earth’s surface, 19-37 miles thick
Structure of the Earth
Earth• Earth is made up of 4 spheres:
• Lithosphere• Atmosphere• Hydrosphere• Biosphere
Atmosphere• The layer of gases
surrounding Earth
• Oxygen we breathe
• Protects the Earth
• Medium for weather and climate
Lithosphere
• Solid rock portion of Earth
• Crust and Upper Mantle
• Forms the seafloor• 30-90 miles thick
HYDROSPHERE• Water elements
of Earth
• Ocean, seas, rivers, lakes, and water in the atmosphere
Biosphere• Part of Earth
where plants and animals live
• Made up of Lithosphere, Atmosphere, and Hydrosphere
Hydrosphere
Atmosphere
Lithosphere
Plate tectonics- enormous moving pieces of the earth’s lithosphere
•Rock in the asthenosphere (upper portion of the mantle) is heated and rises toward the lithosphere, cools and circulates downward
Plate Tectonics
http://www.youtube.com/watch?v=ryrXAGY1dmE&feature=related
Divergent- plates move apart, spreading horizontallyoEx. Saudi Arabia and Egypt (make the Red Sea even
wider)
Rift Valley – if the land is above water
Sea Floor Spreading – when the land is below water
Divergence – Moving Apart
www.aucegypt.edu/faculty/ hamroush/images/Geol...
Great Rift Valley in Africa
(spreading apart)
Convergent- plates collide, causing either one plate to dive under the other or the edges of both plates to crumbleoEx. plate in which India is located is crashing
against the Asia plate causing the Himalayas
Subduction- the heavier plate will sink and the lighter will rise to the surface
Convergence – Moving TogetherTrenches
Mountains
Structural Mountains
Volcanic Mountains
Andes Mountains
redtailcanyon.com/items/6503.aspx
Transform- plates slide past one anotheroEx. San Andreas fault in CA
If the rock isn’t flexible, it will cause a fault
San Andreas Fault in California
geography.sierra.cc.ca.us/ booth/California/1_...
•65 million years ago, Pangaea split apart
•Because the sea floor was expanding (newer fossils were found in the middle of the ocean
Continental Drift