Earthquake Faults, Historical Earthquakes, and Earthquake Preparedness. Craig depolo Nevada Bureau of Mines and Geology

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1 Earthquake Faults, Historical Earthquakes, and Earthquake Preparedness Craig depolo Nevada Bureau of Mines and Geology

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4 Earthquake Jack in the Box Analog Earthquake Faults = box and spring (bigger the box larger Jack is) Constant Deformation of Crust = turning the crank Earthquake = Jack

5 Quaternary Fault Map of Nevada 1500 faults across the state Potential Earthquake Sources

6 Two General Types of Faults in Nevada Normal Dip-Slip faults Strike-Slip faults

7 Normal Dip-Slip Faults (very few active reverse dip-slip faults)

8 1954 Dixie Valley earthquake

9 Peavine Peak fault - north side of Peavine Mountain

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11 Fault set-back zone in Las Vegas

12 Fault Scarps Mt. Rose Highway Photo by Burt Slemmons

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14 1979 Imperial Valley, CA earthquake 1992 Landers, CA earthquake

15 1992 Landers Earthquake

16 1992 Landers, CA Earthquake, M7.3 Right-Lateral Strike-Slip Movement

17 depolo (2008)

18 How Big is an Earthquake? Magnitude 3 - football field of rupture Magnitude 4 - half a mile of rupture Magnitude 5 - a couple miles of rupture Magnitude 6-6ish miles of rupture Magnitude 7-10s of miles of rupture

19 Earthquakes in and around Nevada 1850s to 2012 MyHazard website

20 Magnitude 4 Earthquakes in Nevada

21 Seismic Belts In Nevada

22 Nevada s Earthquake History

23 Pre-1900 Major Earthquakes Year Mag. Location State Elapsed Time NV M s? 7+? Owens V. region CA s 7? N-central NV NV ? 6+? Pyramid Lake NV Sierraville CA N of L. Tahoe CA-NV SW of Pyramid L. NV 3 yr 1868(2) 6 S of Reno NV 8 yr /20 sec S of Reno NV 1.25 yr S of Reno NV 8 hr Austin NV Owens V. CA 2.3 yr Owens V. CA (3.5 hr) N. Owens V. CA (8 days) Round V. CA (8 days) ? Austin NV 7 mo Eureka NV Diamond M. CA (2.75 yr) Susanville CA (10 yr) Carson City NV 15 yr Susanville CA (2 yr)

24 20 th Century Major Earthquakes Year Mag. Location State Elapsed Time NV M Elko NV ? Wonder NV 16 yr S of Columbus M. NV 2 yr Reno NV 3.25 yr Reno NV 65 days S of Winnemucca NV 1.5 yr S of Winnemucca NV 5 hr E of Death V. CA (2.5 yr) Cedar M. NV 17 yr Wabuska NV 6 mo Excelsior M. NV 5 mo Verdi CA-NV 14 yr Fort Sage M. CA -

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27 20 th Century Major Earthquakes Year Mag. Location State Elapsed Time NV M E of Fallon NV 6 yr E of Fallon NV 11 hr E of Fallon NV 49 days Fairview P. NV 3 mo Dixie V. NV 4.3 min Truckee CA 22 yr Caliente NV Mammoth L. CA (14 yr) Mammoth L. CA (16 min) Mammoth L. CA (2.9 hr) Mammoth L. CA (1.8 days) Chalfant V. CA (6 yr) Eureka V. CA (7 yr)

28 21 st Century Major Earthquakes Year Mag. Location State Elapsed Time M Wells NV 42 yr W of Reno NV

29 Wells old town before the earthquake Photo by Jack Hursh

30 2008 Wells Earthquake Magnitude 6.0, 30 to 40 seconds of shaking (basin response), Began with a loud bang; explosion like, Epicenter was 5.6 mi NE; ruptured to within 1.2 mi of town, Early morning event.

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32 Wells old town after the earthquake

33 Wells Earthquake Damage 35 out of ~80 buildings damaged (44%), 10 had severe or heavy damage (13%), 3 out of ~450 homes were severely damaged, >60 chimneys were damaged (10-15%).

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43 1915 Pleasant Valley Earthquake; M 7.3 Modified Mercalli Intensity Map Modified from Stover and Coffman, 1993

44 1915 Pleasant Valley, Nevada Earthquake M miles of surface rupture

45 1915 Pleasant Valley M 7.3 Ground offset about 15 feet vertical Created waterfall from new spring flow

46 1915 earthquake tank damage Lovelock 42 miles away from earthquake

47 1995 Kobe, Japan Earthquake

48 1994 Northridge, California Earthquake

49 1994 Northridge, California Earthquake

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51 Great Nevada ShakeOut

52 Nevada s Earthquake History

53 Return to Nevada s Earthquakes

54 Period of low belief In the earthquake threat

55 EARTHQUAKE! Drop, Cover, and Hold When the shaking stops, assess your surroundings; help others, replace telephones, move out of the building if you need to and it is safe to do so Do not use elevators

56 EARTHQUAKE! Is everybody safe and accounted for? Are there any hazards? Fires, damaged building, gas leaks, water leaks; if so turn off Check on your neighbors Help each other out, comfort each other

57 EARTHQUAKE! Prepare to be on your own for a while Be aggressive in cleaning up messes and helping others clean up (recovery); have a pioneering spirit

58 What are you going to do? There is a potential for a loss of power, water, communication, and sewer for three to five days; possible damaged house. Power: flashlights and batteries, refrigerator and freezer strategy, generator, use daylight, blankets, briquettes

59 Water: water heater supply, stored water, toilet reservoir Communication: telephones for emergencies only, 911 for emergencies only, internet can be up, after emergency response text out-of-state contact, pre-communicate areas to meet post-eq. Temporary Housing: family, friends, camping tent, shelters, out-of-area hotel Food & Meds: five days supply; camp stove

60 Five Steps to Earthquake Safety

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62 Dane Golden / FEMA News Photo Do Not Run Out Of A Building During An Earthquake!!!

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68 Nevada is Earthquake Country

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