A. Break up of Pangaea

1. Triassic
   1. open central Atlantic
   2. split Gondwana into two pieces
2. Jurassic
   1. open southern Atlantic (separate S. America and Africa)
   2. India breaks off
3. Cretaceous
   1. open north Atlantic (west of Greenland)
   2. split Antarctica and Australia
4. Tertiary
   1. north Atlantic shifts eastward
   2.  India continues rapidly northward

B. Global orogenies

1. Alpine orogeny
2. Himalayan orogeny

C.  Evolution of western cordillera

1. accreted terranes
1. adding micro-continents, island arcs, etc onto continent at subduction zone
2. suture zones, ophiolites, serpentinite
2. Nevadan orogeny
1. subduction zone as Pangaea breaks up and N. America moves west
2. late Jurassic to mid-Cretaceous
3. forms granic rocks of Sierra Nevada
3. Laramide orogeny
1. shallow subduction of young, warm, buoyant ocean plate
2. late Cretaceous to mid-Tertiary
3. caused uplift of Rockies and western cordillera
4. San Andreas
1. interaction of subduction zone and spreading center
2. transform boundary
3. began 29 ma
4. release compression on western US
5. Basin and Range
1. normal faults
2. extension caused by relaxation and/or spreading
3. mid-Tertiary to present

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