Download convection - swiftscience

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Plate tectonics
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* Light/less dense
* Hot
* Heavy, denser
* cold
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*Define
*Draw a pic
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*Why?
*Density differences (less dense
rises, denser sinks)
Less dense
(warmer)
*
more dense (colder)
*what is causing
convection?
* what is causing the
air to heat up?
*The sun is a heat
source.
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heat source
*Where does convection occur?
*Water
*Air
*Mantle
*Sun
University of Wisconsin – Green Bay
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*What is convection transferring?
*Convection transfers heat & energy by
movement through fluids (gas, liquids)
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*Lithos
* stone, rock
*Crust + upper part of upper mantle
*Rigid, brittle
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Plates (tectonic plate)
•Ex: North American plate, Pacific
plate, Juan de Fuca plate, etc.
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*DEFINITION
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*Astheno
*weak, soft
*rock
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*Zone of weak, soft rock
*Plastic-like
*Lithosphere (plates) float on top
*DEFINITION
*DRAW LITHOSPHERE &
ASTHENOSPHERE
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*Place (zone) where the plate descends
*Cold, denser plate
*Convergent boundary
*definition
*Simple drawing
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*Slab push
*Divergent boundary, seafloor spreads,
mid-ocean ridge
*Slab pull
*cold, dense plate subducting & pulls the
plate into the subduction zone
*Draw simple diagram
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*Plates are in
constant motion
*~20 plates
*driven by
convection
currents in the
mantle
*Move few cm
per year
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Density differences: “wax on–wax off” circular motion
Heat source: heat from the core and radioactive decay
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*Continental drift evidence
*Seafloor spreading evidence
*Earthquakes and volcano activity –
concentrated zones plate
boundaries
*Measure plate motion through GPS
*Hot spots – show plate movement
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*DEFINE HOT SPOTS
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