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Week 7: Feb. 28 - March 3

Igneous rocks of convergent margins
  • Review of subduction zones (trench, accretionary prism, volcanic arc, forearc, backarc, mantle wedge, Wadati-Benioff zone, etc.)
  • Apparent problem of generating magma where cold material is being subducted
  • Rock types in ocean-ocean convergent margins and the question of primary magmas
  • Melting of the mantle wedge by addition of water and lowering of solidus
  • Source of water in subduction zones
  • immature and mature island arcs
  • origins of more silicic magmas in island arcs
  • assimilation and fractional crystallization
  • origins of granitic batholiths

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