IX. San Andreas System

A. Origin
  1. Mendocino triple junction
  2. Cascadia subduction zone (Gorda plate)
    1. seismicity
    2. fold-thrust belt
B. Geometry 
  1. fault strands
  2. offset streams
  3. restraining bend
    1. compression
    2. ridges
    3. reverse faults or thrust faults
    4. folding
  4. releasing bend
    1. extension
    2. sag ponds
    3. pull apart basins
C. History
  1. northern San Andreas
    1. Mendocino to Hollister
    2. 4 major strands: Rodgers Creek, Hayward, Calaveras
    3. various reverse faults
    4. 1989 Loma Prieta M7.1 - strike slip and reverse motion
    5. 1906 San Francisco M 8.2? - 430km of ground rupture
    6. sediment related damage
  2. central San Andreas
    1. fault creep releases strain ( around 1cm per year)
    2. Parkfield - 22 year recurrence of M6 (overdue)
  3. Carrizo Plain
    1. 1857 Fort Tejon M8.2?
  4. Big Bend - Transverse ranges
    1. restraining bend
    2. reverse faults and thrust faults
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