Transcript of Plate Tectonics. In This Chapter: Composition of the Earth Layers of the Earth: crust, outer core,...
- Slide 1
- Plate Tectonics
- Slide 2
- In This Chapter: Composition of the Earth Layers of the Earth:
crust, outer core, inner core, mantle Continental Drift Theory
Evidence: fossil clues, climate clues, rock clues Pangaea Theory of
Seafloor Spreading Evidence: rock and magnetic clues Plate
Tectonics Plate movements Plate boundaries Convection currents
- Slide 3
- Fossil Rock Anthem
http://www.youtube.com/watch?v=ClJ5lwl_wM0
- Slide 4
- Continental Drift Theory Proposed by Alfred Wegner Continents
were at one time all joined together (Pangaea)
- Slide 5
- Pangaea http://3dparks.wr.usgs.gov/nyc/images/fig83.jpg
- Slide 6
- Clues to Pangaea Fossil Clues Reptile Mesosaurus Fern
Glossopteris
http://www.fossilmall.com/EDCOPE_Enterprises/plants/plfossil29/GLOSSOPTERIS-L.jpg
http://www.greatsouth.net/fossil_replicas/images_fossil_replicas/frp100.jpg
- Slide 7
- Clues to Pangaea Climate Clues Fossils of warm water plants
found on Arctic Ocean island (Glossopteris) Glacial deposits &
grooved bedrock in South America, Africa, India, and Australia
These areas were once connected
http://upload.wikimedia.org/wikipedia/commons/thumb/6/67/Pangaea_Glossopteris.jpg/220p
x-Pangaea_Glossopteris.jpg
- Slide 8
- Clues to Pangaea Rock Clues Similar rock structures are found
on different continents Ex. Appalachian Mountains: Eastern U.S.
Greenland Western Europe
http://www.jamestown-ri.info/Pangaea_mts.jpg
- Slide 9
- How Do The Continents Drift? Theory of Seafloor Spreading
supports Wegeners theory
http://mail.colonial.net/~hkaiter/Aaa_web_images2012/sfsseafloor_spreading.gif
- Slide 10
- Theory of Seafloor Spreading Proposed by Harry Hess in 1960s
Hot, less dense material in mantle is forced upward to surface at
Mid Ocean Ridge It cools, contracts, turns, and flows sideways,
carrying the seafloor away from the ridge in both directions MAGMA!
Moves upward, flows into cracks, solidifies to form new
seafloor
- Slide 11
- Evidence of Seafloor Spreading Age difference in rocks Glomar
Challenger (research ship) found youngest rocks are near center of
ridges Magnetic clues Magnetic field has reversed itself
http://www.gcsescience.com/Magnetic-Reversal-Mid-Ocean-Ridge.gif
- Slide 12
- Plate Tectonics Plate movements The Earths crust and upper
mantle are broken into sections called plates
http://www.enchantedlearning.com/egifs/Earthsplates.GIF
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- Earths Composition Lithosphere Upper mantle and crust Rigid,
less dense than material below it; divided into plates Floats on
asthenosphere Asthenosphere Located below lithosphere More dense,
plastic-like
- Slide 14
-
http://www.physicalgeography.net/fundamentals/images/lithosphere.gif
- Slide 15
- Plate Boundaries Divergent Boundary (divide) Plates move away
from each other
http://geographicalconcepts.wikispaces.com/file/view/db.jpg/177810579/db.jpg
- Slide 16
- Plate Boundaries Convergent Boundary One fault surface is
forced up and over the other fault surface Forms mountains &
subduction zones
http://www.geo.cornell.edu/hawaii/220/PRI/images/subduction2.jpg
- Slide 17
- Plate Boundaries Transform Boundary Plates slide past each
other Not much upward/downward movement
http://www.divediscover.whoi.edu/images/tectonics-slide.jpg
- Slide 18
- Causes of Plate Tectonics
http://rockdale.k12.ga.us/schools/dms/class/jtamburro/Class%20Documents/Geology%20Unit/Convection%20current.JPG
- Slide 19
- Effects of Plate Tectonics Volcanoes Earthquakes Mountain
building Ocean rift formation Tsunamis Ocean basins
- Slide 20
- Review What are the 3 types of clues for Pangaea? Who proposed
the Continental Drift Theory? What theory did Harry Hess propose?
What is the difference between the lithosphere and
asthenosphere?
- Slide 21
- References Glencoe McGraw-Hill,. Earth Science. 2007. Print.
http://geographicalconcepts.wikispaces.com/file/view/db.jpg/177810579/db.jpg
http://mail.colonial.net/~hkaiter/Aaa_web_images2012/sfsseafloor_spreading.gif
http://rockdale.k12.ga.us/schools/dms/class/jtamburro/Class%20Documents/Geology%20Unit/Convection%20current.JPG
http://upload.wikimedia.org/wikipedia/commons/thumb/6/67/Pangaea_Glossopteris.jpg/220px-Pangaea_Glossopteris.jpg
http://3dparks.wr.usgs.gov/nyc/images/fig83.jpg
http://www.divediscover.whoi.edu/images/tectonics-slide.jpg
http://www.enchantedlearning.com/egifs/Earthsplates.GIF
http://www.fossilmall.com/EDCOPE_Enterprises/plants/plfossil29/GLOSSOPTERIS-L.jpg
http://www.gcsescience.com/Magnetic-Reversal-Mid-Ocean-Ridge.gif
http://www.geo.cornell.edu/hawaii/220/PRI/images/subduction2.jpg
http://www.greatsouth.net/fossil_replicas/images_fossil_replicas/frp100.jpg
http://www.jamestown-ri.info/Pangaea_mts.jpg
http://www.physicalgeography.net/fundamentals/images/lithosphere.gif
http://www.youtube.com/watch?v=ClJ5lwl_wM0