• Mesozoic/Cenozoic tectonics comprise half of a Wilson Cycle.
  • The Atlantic & Indian Oceans began opening during the Jurassic Period & have continued opening during the Cretaceous Period and the Cenozoic Era.
  • The Mesozoic-Cenozoic tectonics of the East Coast of North America is dominated by exotic terrane accretion.
  • The Mesozoic-Cenozoic tectonics of the West Coast of North America is dominated by suspect terrane accretion.
  • The Mesozoic-Cenozoic tectonics of the West Coast of North America is dominated by rifting and subsidence.
  • The Mesozoic-Cenozoic tectonics of the East Coast of North America is dominated by rifting and subsidence.
  • The Mesozoic-Cenozoic Nevadan, Sevier & Laramide Orogenies of the West Coast of North America have all been caused by subduction of Pacific Ocean oceanic lithosphere.
  • The Triassic was characterized by seafloor spreading.
  • The oldest seafloor in the central North Atlantic Ocean is 190 my old & represents the initial breakup of Wegener's Pangea into Laurasia & Gondwana.
  • The oldest seafloor in the South Atlantic Ocean is 190 my old & represents the initial breakup of Wegener's Pangea into Laurasia & Gondwana.
  • The oldest seafloor in the central North Atlantic Ocean is Middle Jurassic (190 my old) & represents the initial breakup of Wegener's Pangea into Laurasia & Gondwana.
  • The oldest seafloor in the Indian Ocean is 165 my old & represents the initial breakup of Gondwana.
  • The oldest seafloor in the western Pacific Ocean is Late Jurassic (165 my old) & represents the initial breakup of Gondwana.
  • The initial breakup of Laurasia began approximately 90 my ago.
  • Greenland separates from Eurasia & joins North America approximately 90 my ago.
  • The late Cenozoic tectonic pattern of the East Coast of North America is characterized by uplift & rifting due North America overrunning the Mid-Atlantic Ridge.
  • The Late Cenozoic tectonic pattern of the West Coast of North America is characterized by uplift & rifting due to North America overrunning the East Pacific Rise.
  • Which of the following statements about the oldest seafloor in the Atlantic Ocean is true?
    • A. The oldest seafloor in the Atlantic Ocean is 135 million years old (Early Cretaceous).
    • B. The oldest seafloor in the Atlantic Ocean is located off the east coast of South America & southwest coast of Africa.
    • C. The oldest seafloor in the Atlantic Ocean marks the location of the initial breakup of Pangea II.
    • D. both A. & B.
  • The oldest seafloor in the ______ Ocean is Late Jurassic (165 my old) & represents the initial breakup of Gondwana.

    A. North Pacific B. South Pacific C. North Atlantic D. South Atlantic E. Indian

  • The oldest seafloor in the ______ Ocean is Middle Jurassic (~190 my old) & represents the initial breakup of Wegener's Pangea into Laurasia & Gondwana.

    A. North Pacific B. South Pacific C. North Atlantic D. South Atlantic E. Indian

  • The oldest oceanic crust in the present oceans is _______ years old.

    A 10 m.y. B. 38 m.y. C. 100 m.y. D. ~200 m.y. E. 3800 m.y.

  • The oldest oceanic crust in the Atlantic Ocean (& also the Pacific Ocean) formed about ___________ million years ago, or in the ______________________ Period [Fill in one or the other].
  • The Mesozoic-Cenozoic Nevadan, Sevier & Laramide Orogenies of the West Coast of North America have all been caused by _______________________ of Pacific Ocean oceanic lithosphere.
  • Matching: Match the beginning of the continental separations listed on the left with the time periods listed on the right. Each item on the right may be used more than once.
    • South America from Africa A. Middle Jurassic (190 million years ago)
    • India from East Gondwana B. Late Jurassic (160 million years ago)
    • Laurasia from Gondwana C. Early Cretaceous (135 million years ago)
    • Greenland from North America D. Late Cretaceous (90 million years ago)
    • East Gondwana from West Gondwana E. Cenozoic (55-60 million years ago)
  • Matching: Match the beginning of the continental separations listed on the left with the time periods listed on the right. Each item on the right may be used more than once. You may use the maps at the front of the room.
    • Africa from South America A. Middle Jurassic (190 million years ago)
    • India/Madagascar from Australia/Antarctica B. Late Jurassic (165 million years ago)
    • Laurasia from Gondwana C. Early Cretaceous (135 million years ago)
    • Australia from Antarctica D. Late Cretaceous (90 million years ago)
    • West Gondwana from East Gondwana E. Cenozoic (45 million years ago)


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