Cascadia Earthquake

Full Rip 9.0

The Next Big Earthquake in the Pacific Northwest

Sandi Doughton Central 551.2209164 D732F 2013

• Science reporter at The Seattle Times

• 1700/01/26 ~21:00 local
• 1964 Alaska 9.2
• 2004/12/26 Indian Ocean Sumatra–Andaman earthquake
• 2011/03/11 Friday Japan Tōhoku

• p001 Satsop Nuclear Power Plant - mostly built

• p008 Juan De Fuca plate 4cm/y to the northeast
• p009 Bpb Yeats 1977 skeptic, Cal Tech Tom Heaton and Hiroo Kanamori, locked plates
• p017 Brian Atwater Neah Bay Grumman canoe
  • Science 236 (1987): 942-44 Evidence for great Holocene earthquakes ...
  • at least six drops in 7000 years, as much as 6 feet in some places
  • Copalis ghost forest, trees drop and buried in silt, correlate tree rings to living "witness" trees upslope
• p019 paleoseismology, Kerry Sieh
• p034 David Yamaguchi Dendrochronologist

• p039 James Gilchrist Swan lived with Makah Indians in 1850s, died 1900. Ivan Doig Winter Brothers

• p046 Kenji Satake at Caltech, Hokkaido University, 1700 tsunami, p048 10 hours from NW to Japan, scaled Cascadia1700 to 9 or above
• p055 OSU Chris Goldfinger, Alvin, seafloor cores of landslides, twice as common off Oregon
• p057 turbidity currents from 1929 mag 7.2 Grand Banks earthquake cut transatlantic cables

• p058 Gary Griggs, underwater landslides 30 stories high, two days to travel 1600 km, turbidites

  • p060 Mt Mazama 7770 Ya ash later for dating, 13 major events since, 300, 690, 1190, 2170, 2780 Ya

• p071 Seattle Fault east west thrust fault, Zdenko Frankenburger Daneš gravity meter

  • Restoration Point and Point Alki, uplift on basalt south, sedimentary on north, Seattle on sediment basin that amplifies quakes
• p079 Underwater forests in Lake Washington and Lake Sammamish, quake 900 to 930 AD
• p087 faults show up with lidar which can see 10% of ground through treetops
• p094 Map, Southern Whidbey Island fault SWIF
• p129 2001 Nisqually "deep" quake, like 1909, 1939, 1946, 1949 (big), 1965
  • perhaps "water reactivating fault"
• p137 Japan, p139 Patrick Corcoran, Cannon Beach (some preparation, probably will be far worse than Japan)
  • p141 125,000 people vulnerable to tsunami from B.C. to Eureka Cal. 10K to 20K dead?
• p141 $1.6B Kamaishi seawall too small
• p143 Seaside OR, a mile to high ground across piling bridges (Corcoran ran route for documentary in 7m33s)
  • "Run for your life 2K", hotel owners won't help
• p185 buildings designed to code, not worst case. Fewer shear walls, often glass outsides and concrete (not steel) core
  • high ceilinged ground floors worse, "nonductile design" breaks
  • Rainier tower with welded (not bolted) steel frame. Welds can be brittle
  • Brick buildings, tiltup slab, pre-1973 concrete buildings will probably fail
• p198 Safeco field, Century field built on 3700 pilings through fill
  • Safeco roof on ball bearings with friction dampers
• Space Needle on single-pour 30 foot deep concrete, overdesigned structural steel, structural engineer John K. Minasian
• p218 laser ranging between south BC mountains, watching millimeter spacing changes
• GPS, "silent quakes", episodic slow tremor and quake in the deep crust
  • increasing strain westward and upward where subduction fault is brittle rather than pliable
• p235 p-waves (pressure) up to 17 kmph, (7.6 km/s ), 2 to 5 minutes before the s (shear) wave (400 to 1500 m/s ???)
  • warning network might cost $200M