Tectonic driving forces

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Tectonic driving forces
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Read Chapter 11, Kearey and Vine
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Consequences of mechanical properties
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all tectonic phenomena
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drivers
gravity
density
temperature composition
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How convection works
equation of vertical motion in a fluid
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How convection works
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Controlling parameters
temperature
gravity
layer thickness
thermal expansion
density
thermal diffusivity
viscosity
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Layered convection?
660 compositional or phase transition?
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Layered convection?
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Layered convection?
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Layered convection?
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Layered convection?
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How does mantle convection interact with plates?
drag only
convection integrated
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Mapping crustal convection
Plates and boundaries

• Earthquakes
• Strain
• Velocity

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Mapping mantle convection

• Geoid
• Seismic velocity
• Heat flow

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How does mantle convection interact with plates?
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scaling
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Forces on plates
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Forces on plates basal traction
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Forces on plates continental traction
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Forces on plates ridge push
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Forces on plates slab pull
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lithosphere-mantle interaction
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Flow directions
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Flow directions
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Midterm

• 1/3 problems, 2/3 short answer
• Equations all provided
• Bring a calculator!
• Problems 1 point for correct equation, 1 point
  for unit analysis, 1 point for the right answer
• Short answer explain or apply basic concepts (no
  reciting facts)