Slide 1

Slide 2

THE GREAT CALIFORNIA SHAKEOUT Sheila Bart, Greg Berger, Georgina Campos, Garland Chen, Jaquelyn Felix, Brandon Green

Slide 3

W HY IS C ALIFORNIA REFERRED TO AS EARTHQUAKE COUNTRY ?

Slide 4

The frequency of earthquakes in California - On average, there are approximately 30 earthquakes each day in California. - Earthquakes of magnitude 6.0 and greater occur approximately every 5 years. - In comparison to the central and eastern sections of the United States, California experiences a greater amount of seismicity.

Slide 5

Fault systems throughout California - The San Andreas Fault system extends from northern California and continues south past the California border and into Mexico. - In addition to the San Andreas Fault system, there are a number of other smaller fault systems throughout the state of California. - The Los Angeles area itself has a number of faults that contribute to both small and relatively large earthquakes.

Slide 6

Works Cited Jones, L., Benthien, M. Putting down roots in earthquake country. Southern California Earthquake Center. 2011. www.earthquakecountry.info/roots/c ontents.html Southern California Earthquake Data Center

Slide 7

W HAT TYPE OF FAULTS EXIST IN C ALIFORNIA ? The answer may surprise you

Slide 8

Normal Faults What is it?Where is it? Caused by extension Outward displacement Death Valley Horst and Graben Elevation: -282 ft

Slide 9

Reverse Faults What is it?Where is it? Caused by compression Inward displacement Transverse Ranges

Slide 10

Strike-Slip Faults What is it?Where is it? Displacement is parallel to fault strike San Andreas Fault

Slide 11

Oblique Faults A combination of strike-slip and reverse thrusting The most common type of fault What is it?

Slide 12

Works Cited Bartolomeo, Eleanor, and Nicole Longinotti. "Tectonic history of the Transverse Ranges: Rotation and deformation on the plate boundary.". UC Davis, n.d. Web. 19 June 2014. Johnson, Jenda. "What are the 4 basic classes of faults?" Incorporated Research Institutions for Seismology. Web. 17 June 2014. http://www.iris.edu/hq/programs/education_and_outreach/animations/2. http://www.iris.edu/hq/programs/education_and_outreach/animations/2 Jordan, Tom, Raymon Siever, and John Grotzinger. "Folds, Faults, and Other Records of Rock Deformation." Understanding Earth. New York: Frank Press, 2003. Print. "Lowest Places on Earth." Death Valley. National Park Service. Web. 17 June 2014. "The San Andreas Fault." USGS. 17 January 2013. Web. 17 June 2014. http://pubs.usgs.gov/gip/earthq3/safaultgip.html.

Slide 13

PLATE BOUNDARIES IN CALIFORNIA

Slide 14

Plate Composition 7 km (4 mi) thick Basalt More dense Varies between 10 and 75 km (6 and 47mi) Granitic rock Less dense OceanicContinental

Slide 15

Plate Boundaries Two plates move apart in opposite directions Think: conveyor belts Magma flows up from the mantle where plates thin Mid-ocean ridges DivergentConvergent Plates pushing into each other Continental Continental Continental Oceanic Oceanic Oceanic DENSITY Mountain formation Subduction

Slide 16

What kind of plate boundaries are found in California? San Andreas fault zone Transform Boundary Pacific plate moves Northwest in relation to NA plate Great 1906 earthquake that destroyed San Francisco Transform Horizontal motion past each other Mostly slide without creating or destroying material Large earthquakes can occur at transform plate boundaries

Slide 17

Works Cited Press, F., Siever, R., Grotzinger, J., Jordan, T. H., 2003, Understanding Earth Understanding Plate Motions. United States Geological Survey: http://pubs.usgs.gov/gip/ dynamic/ understanding.html, May 2012.http://pubs.usgs.gov/gip/

Slide 18

Explain how focal mechanisms can be determined from earthquake data?

Slide 19

What are focal mechanisms?

Slide 20

Slide 21

How are they calculated?

Slide 22

What does this all mean? Faulting geometry identification Look theyre beach balls!

Slide 23

compression vs. dilatation

Slide 24

Slide 25

Slide 26

Works Cited Cronin, Vince, 2004, A Draft Pimer on Focal Mechanism Solution for Geologists, p. 1-14 USGS, 1996. Focal Mechanisms. Learn: Earthquake topics for Education..http://earthquake.usgs.gov/learn/topics/beachball.php IRIS, 2012. Focal Mechanisms Explained..http://www.youtube.com/watch?v=MomVOkyDdLo Merriam-Webster, 2014. the Dictionary. http://www.merriam-webster.com/dictionary/dilatation California Institute of Technology, 2014. San Jacinto Fault Zone. http://www.data.scec.org/significant/sanjacinto.html Springer Link, 2011. Earthquake, Focal Mechanism. http://link.springer.com/referenceworkentry/10.1007%2F978-90-481-8702-7_158/fulltext.html openSHA, 1980. Strike, Dip, and Rake (focal Mechanism). http://www.opensha.org/glossary-strikeDipRake Calvin College. Eachquakes: A World in Motion. Recent Quakes, Calvin Seismograph http://www.calvin.edu/academic/geology/seismology/

Slide 27

Slide 28

What is a Major Earthquake? Magnitude Intensity Richter Magnitude Moment Magnitude measures the energy released at the source of the earthquake and it is determined from measurements on seismographs. takes the amplitude and distances of seismograms and is known to underestimate the size of large quakes. measures the strength of shaking produced by the earthquake at a certain location and it is evaluated from effects on people, human structures, and the natural environment. Magnitude is related to the physical parameters that uses seismic moment (Mo), the force needed to generate the recorded waves, determines the energy released by the quake. M W = 2/3 log10(M O ) - 10.7

Slide 29

What is a Major Earthquake?

Slide 30

San Francisco Earthquake 1906 5:12 AM - April 18, 1906 Magnitude: 7.8 Intensity: maximum intensity of XI was based on geologic effects, but the highest intensity based on damage was IX. Rupturing about 430 km or more to the northernmost of the San Andreas Fault The earthquake was felt from southern Oregon to south of Los Angeles and inland as far as central Nevada. Due to water pipe breakage, the water was shut off. Since there was no water, the fire got set off causing a large part of San Francisco to burn down.

Slide 31

Major Earthquakes since 1906 DateEarthquakeMagnitudeFaults 18 April 1906 San FranciscoM L 7.8San Andreas 4 Nov. 1927 Offshore Lompoc M L 7.1Hosgri 21 July 1952 Kern CountyM w 7.5White Wolf 28 June 1992 LandersM w 7.3Johnson Valley, Kickapoo, Homestead Valley, Emerson, and Camp Rock 18 Oct. 1999 Hector MineM w 7.1Hector Mine (Lavic Lake) and Bullion (Pisgah)

Slide 32

Faults Involved... Type of FaultEarthquake Fault Names Right-Lateral Strike Slip Landers Johnson Valley, Landers, Homestead Valley, Emerson, and Camp Rock faults Hector Mine Lavic Lake and Bullion Reverse with some Left-Lateral Kern CountyWhite Wolf Reverse and ThrustLompoc Hosgri

Slide 33

Works Cited Historical Earthquakes: San Francisco 1906. USGS: Earthquake Hazards Program. 1 November 2012. Web. 16 June 2014.. Hector Mine Earthquake. Southern California Earthquake Data Center. Caltech, 31 January 2013. Web. 16 June 2014.. Kern County Earthquake. Southern California Earthquake Data Center. Caltech, 31 January 2013. Web. 16 June 2014.. Lompoc Earthquake. Southern California Earthquake Data Center. Caltech, 31 January 2013. Web. 16 June 2014.. Landers Earthquake. Southern California Earthquake Data Center. Caltech, 31 January 2013. Web. 16 June 2014.. Measuring the Size of an Earthquake. USGS: Earthquake Hazards Program. 1 November 2012. Web. 16 June 2014.. Zoback, Mary Lou. The 1906 Earthquake and a Century of Progress in Understanding Earthquakes and their Hazards. GSA Today April/May. 2006: 1-11. Print.

Slide 34

What is Drop, Cover and Hold on and who is participating?

Slide 35

ShakeOut: Drop, Cover, and Hold On. 11 million participants (US & other countries) 7,200,000 from California 830,000 from Japan Who is Participating? K-12 School Districts Colleges and Universities Businesses Government Institutions

Slide 36

What is Drop, Cover, and Hold on? Actions to take during an earthquake: DROP to the ground COVER by getting under a sturdy desk or table HOLD ON to it until the shaking stops

Slide 37

Works Cited Shakeout Drop, Cover, and Hold On: http://www.shakeout.org/dropcoverholdon/