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discuss the elastic rebound theory
California Science ContentStandards Covered:California Science ContentStandards Covered:
►Plate tectonics operating over geologictime has changed the patterns of land,sea, and mountains on Earth's surface.As the basis for understanding thisconcept:►Plate tectonics operating over geologictime has changed the patterns of land,sea, and mountains on Earth's surface.As the basis for understanding thisconcept:
►3D: Students know why and howearthquakes occur and the scales usedto measure their intensities &magnitude►3D: Students know why and howearthquakes occur and the scales usedto measure their intensities &magnitude
Terms Chapter 6Define and write sentences or draw picturesTerms Chapter 6Define and write sentences or draw pictures
1.Earthquakes1.Earthquakes
2.Elastic reboundtheory2.Elastic reboundtheory
3.Aftershocks3.Aftershocks
4.Focus4.Focus
5.Epicenter5.Epicenter
6.Pacific ring of fire6.Pacific ring of fire
7.Fault zones7.Fault zones
8.Seismograph8.Seismograph
9.P waves
10.S waves
11.Surface waves
12.Magnitude
13.Microquakes
14.Mercalli scale
15.Intensity
16.Tsunami
17.Seismic gaps
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discuss the elastic rebound theory
2/11/20162/11/2016
discuss the elastic rebound theorydiscuss the elastic rebound theory
EarthquakesEarthquakes
Chapter 6Chapter 6
3D: Students know why and how earthquakes occur and the scales used to measuretheir intensities & magnitude3D: Students know why and how earthquakes occur and the scales used to measuretheir intensities & magnitude
Elastic Rebound TheoryElastic Rebound Theory
Anatomy of a QuakeAnatomy of a Quake
Epicenter, focus, seismic wavesEpicenter, focus, seismic waves
Fore, primary, aftershockFore, primary, aftershock
Shallow, intermediate & deep focusShallow, intermediate & deep focus
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discuss the elastic rebound theory
Lecture 6.1Discuss elastic rebound theoryLecture 6.1Discuss elastic rebound theory
►Elastic Rebound Theory►Elastic Rebound Theory
When a STRESS is applied, the road changes from its originalform – ELASTIC DEFORMATIONWhen a STRESS is applied, the road changes from its originalform – ELASTIC DEFORMATION
When the RUPTURE relieves the STRESS, the ground under theroad REBOUNDS and returns to its original conditionWhen the RUPTURE relieves the STRESS, the ground under theroad REBOUNDS and returns to its original condition
When the RUPTURE occurs, we feel the EARTHQUAKEWhen the RUPTURE occurs, we feel the EARTHQUAKE
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discuss the elastic rebound theory
Lecture 6.1Discuss elastic rebound theoryLecture 6.1Discuss elastic rebound theory
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Explain why earthquakes generally occurat plate boundariesExplain why earthquakes generally occurat plate boundaries
►Slippage first occurs at the FOCUS►Slippage first occurs at the FOCUS
►The place on the SURFACE of the Earthunder the focus is the EPICENTER►The place on the SURFACE of the Earthunder the focus is the EPICENTER
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discuss the elastic rebound theory
Explain why earthquakes generally occurat plate boundariesExplain why earthquakes generally occurat plate boundaries
►90% of earthquakes have a SHALLOWfocus►90% of earthquakes have a SHALLOWfocus
►Intermediate and deep focusearthquakes (10%) occur 70 Km andDEEPER►Intermediate and deep focusearthquakes (10%) occur 70 Km andDEEPER
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discuss the elastic rebound theory
Explain why earthquakes generally occurat plate boundariesExplain why earthquakes generally occurat plate boundaries
►How does the depth of earthquakes explainthe type of a boundary?►How does the depth of earthquakes explainthe type of a boundary?
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discuss the elastic rebound theory
Explain why earthquakes generally occurat plate boundariesExplain why earthquakes generally occurat plate boundaries
►3 Major Earthquake Zones►3 Major Earthquake Zones
Mid Ocean Ridges – mainly divergentMid Ocean Ridges – mainly divergent
Eurasian-Melanisian Belt – mainly convergentEurasian-Melanisian Belt – mainly convergent
Ring of Fire – mainly convergentRing of Fire – mainly convergent
►Each dot represents an EARTHQUAKE ZONE►Each dot represents an EARTHQUAKE ZONE
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End Lecture 6.1End Lecture 6.1
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discuss the elastic rebound theory
Chapter 6 Section 2 ObjectivesChapter 6 Section 2 Objectives
1.We will be able to compare the three typesof seismic waves.1.We will be able to compare the three typesof seismic waves.
2.We will discuss the method scientist use topinpoint an earthquake.2.We will discuss the method scientist use topinpoint an earthquake.
3.We will discuss the method mostcommonly used to measure the magnitudeof earthquakes.3.We will discuss the method mostcommonly used to measure the magnitudeof earthquakes.
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discuss the elastic rebound theory
Recording EarthquakesLecture 6.2Recording EarthquakesLecture 6.2
►Seismic waves arerecorded on aseismograph►Seismic waves arerecorded on aseismograph
►3 Major forms of wavesrecorded byseismograph►3 Major forms of wavesrecorded byseismograph
P WavesP Waves
S WavesS Waves
Surface WavesSurface Waves
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P WavesP Waves
► aka Primary Waves► aka Primary Waves
►Travel the fastest►Travel the fastest
►Same direction as particle motion►Same direction as particle motion
►Travel FASTER through DENSER material►Travel FASTER through DENSER material
►Move through solids, gases and liquids►Move through solids, gases and liquids
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discuss the elastic rebound theory
S WavesS Waves
► aka secondary or shear waves► aka secondary or shear waves
►SLOWER than P Waves►SLOWER than P Waves
►Travel at RIGHT Angles to particles inmotion►Travel at RIGHT Angles to particles inmotion
►CANNOT pass through liquid or gases►CANNOT pass through liquid or gases
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discuss the elastic rebound theory
How to find the epicenterHow to find the epicenter
►Method: TRIANGULATION►Method: TRIANGULATION
►Must have three (3) seismographs►Must have three (3) seismographs
►Calculate the difference in P wave travelfrom all three►Calculate the difference in P wave travelfrom all three
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discuss the elastic rebound theory
2/11/2016
discuss the elastic rebound theory
Triangulation – Where is the epicenterlocated?Triangulation – Where is the epicenterlocated?
This map shows how the epicenter of the Loma Prieta earthquake was determined usingdata from three seismic stations. The seismogram at Eureka, CA indicated that the epicenterwas 478 km away (red circle). The green circle represents the distance of the epicenter (624km) from Las Vegas. The blue circle represents the distance of the epicenter (702 km) fromElko, NV. The epicenter is determined by the intersection of all three circles near SantaCruz, CA. This triangulation technique requires data from at least three seismicstations in order to determine the epicenter.
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discuss the elastic rebound theory
Earthquake MeasurementEarthquake Measurement
►Magnitude is a measure ofENERGY RELEASED IN ANEARTHQUAKE►Magnitude is a measure ofENERGY RELEASED IN ANEARTHQUAKE
Measured by a RICHTER SCALEMeasured by a RICHTER SCALE
►Intensity is the amount ofDAMAGE an earthquakecauses►Intensity is the amount ofDAMAGE an earthquakecauses
Measured by the MERCALLISCALEMeasured by the MERCALLISCALE
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Lecture 6.2Lecture 6.2
►Big Idea Question #2►Big Idea Question #2
What is the difference between intensity andmagnitude? What scales are used to measure each?What is the difference between intensity andmagnitude? What scales are used to measure each?
►End of Chapter Questions►End of Chapter Questions
p. 112-113 #8-11 p. 112-113 #8-11
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TEST QUESTION:Circle on the diagram the location of theepicenterTEST QUESTION:Circle on the diagram the location of theepicenter
The seismogram in Pusan, Korea indicated that the epicenter was 549 km away (red circle). The green circle represents thedistance of the epicenter (435 km) from Tokyo. The blue circle represents the distance of the epicenter (697 km) from Akita,Japan. The epicenter is determined by the intersection of all three circles in Kobe. This triangulation technique requires datafrom at least three seismic stations in order to determine the epicenter.
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Essential Questions Chapter 6Section 3Essential Questions Chapter 6Section 3
►Describe the possible effects of a majorearthquake on buildings►Describe the possible effects of a majorearthquake on buildings
►Discuss the relationship of tsunamis toearthquakes►Discuss the relationship of tsunamis toearthquakes
►List safety rules follow when an earthquakestrikes►List safety rules follow when an earthquakestrikes
►Identify changes in the earth’s crust that maysignal earthquakes►Identify changes in the earth’s crust that maysignal earthquakes
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identify changes in the earth’s crust that maysignal earthquakes
Describe the possible effects of amajor earthquake on buildingsDescribe the possible effects of amajor earthquake on buildings
►Earthquake Damage►Earthquake Damage
►Most injuries, result ofcollapsing buildings or fallingobjects.
►Types of damage –landslides, fires, broken gasand electric lines, flooding,and damage to dams
►The longer an earthquakelast the more damage itcauses
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identify changes in the earth’s crust that maysignal earthquakes
Describe the possible effects of amajor earthquake on buildingsDescribe the possible effects of amajor earthquake on buildings
►Destruction tobuildings and property►Destruction tobuildings and property
►Buildings are notdesigned to sway, wallscan collapse, may tipover
►Type of ground, solidground offers moresupport to buildings,loose soil can causemore swaying inbuildings
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identify changes in the earth’s crust that maysignal earthquakes
Discuss the relationship of tsunamis toearthquakesDiscuss the relationship of tsunamis toearthquakes
►Tsunamis►Tsunamis
►Caused by underwaterearthquakes, that eithercause a landslide orfaulting underwater.
►Faulting can changeseafloor elevation,forcing the water tomove up and down.
►Underwater landslidecan cause this same upand down motion.
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identify changes in the earth’s crust that maysignal earthquakes
Discuss the relationship of tsunamis toearthquakesDiscuss the relationship of tsunamis toearthquakes
►Tsunamis►Tsunamis
►There is an earlywarning system to alertareas of tsunamis.
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identify changes in the earth’s crust that maysignal earthquakes
List safety rules follow when anearthquake strikesList safety rules follow when anearthquake strikes
►Earthquake Safety►Earthquake Safety
►Before an earthquake
Be prepared – havecanned food, bottledwater, flashlights,batteries and a portableradio.
Plan what to do when aearthquake happens
Learn how to turn off gas,water and electricity tothe house.
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identify changes in the earth’s crust that maysignal earthquakes
List safety rules follow when anearthquake strikesList safety rules follow when anearthquake strikes
►Earthquake Safety►Earthquake Safety
►During an earthquake
Stay calm and get to asafe position
Indoors – protectyourself from fallingobjects.
Outside – stay awayfrom tall buildings,power lines, bridges, ortunnels
2/11/2016
identify changes in the earth’s crust that maysignal earthquakes
List safety rules follow when anearthquake strikesList safety rules follow when anearthquake strikes
►Earthquake Safety►Earthquake Safety
►After the earthquake
Check for hazards,always wear shoes,and avoid power lines
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identify changes in the earth’s crust that maysignal earthquakes
Identify changes in the earth’s crust that maysignal earthquakesIdentify changes in the earth’s crust that maysignal earthquakes
►Earthquakewarnings &predictions►Earthquakewarnings &predictions
►Animals behavior & past earthquakes usedto predict future earthquakes, may be yearsoff
►Fault stress measured to determine seismicgaps, to determine where a quake mayhappen.
►Instruments used to detect crust tilting, rockstress, water flow changes, electro magneticchanges to predict earthquakes.
►Decreases in P-wave speed may tell when aquake is coming.
►Most methods are not very reliable inpredicting an earthquake