EARTHQUAKEAND
FAULTS
ThePhilippines lies
inthePacificringof
fire.
TheRingofFire, alsoreferred toas the Circum-PacificBelt, isapathalong
thePacificOceancharacterizedbyactivevolcanoes andfrequent
earthquakes. ThemajorityofEarth’svolcanoes andearthquakestake
placealongtheRingofFire.
HOWFAULTSAREFORMED?
Faultsarefracturesonthe
surfaceofEarththatresultto
somedisplacementorchangesin
thepositionofrocks.
TYPESOFFAULTS
NORMALFAULT
REVERSEFAULT
THRUSTFAULT
RIGHTANDLEFTSTRIKESLIPFAULTS
ACTIVEFAULTS
INACTIVEFAULTS
NORMALFAULT
Formedwhen
thefootwall
movesup
relativetothe
hangingwall.
REVERSEFAULT
FORMEDWHEN
THEFOOTWALL
MOVESDOWN
RELATIVETOTHE
HANGINGWALL.
THRUSTFAULT
HASA
VERYLOW
ANGLEOF
DISPLACE
MENT.
RIGHTANDLEFTSTRIKESLIPFAULTS
FORMEDTHERE’S
NOVERTICAL
DISPLACEMENT.
ACTIVEFAULTS
THOSETHATHAVEMOVEDONE
ORMORETIMESINTHELAST
10,000YEARS.
INACTIVEFAULTS
THOSETHATHAVENOT
MOVEDFORTHELAST
10,000YEARS.
EARTHQUAKES
Anearthquakeistheshakingofthesurfaceofthe
earthduetothesuddenreleaseofenergyinthe
earth'scrust.Asaresult,seismicwaves(also
knownasSwaves)arecreated.Theseismic
activitiesinanareadeterminethetypeand
intensityoftheearthquake.
2TYPESOFEARTHQUAKE
TECTONIC
VOLCANIC
TECTONIC
EARTHQUAKEAREPRODUCEDBY
SUDDENMOVEMENTALONGFAULTS
ANDPLATEBOUNDARIES.
VOLCANIC
EARTHQUAKEINDUCEDBY
RISINGLAVAORMAGMA
BEANETHACTIVEVOLCANOES.
HOW
EARTHQUAKES
FORMED?
Earthquakesarevibrationsof
theearthcausedbyrapidrelease
ofenergy.
Theyoccurwhentheforcesare
appliedtorocks,thusbending
andbreakingthem.
FOCUS
Thefocusofanearthquakeisthe
pointwheretherocksstartto
fracture.
Itistheoriginoftheearthquake.
EPICENTER
Theepicenteristhepointonland
directly,abovethefocus.
Usuallythelocationthatis
reportedtothepublic.
MAGNITUDE
Measuretheenergyreleasedatthe
sourceoftheearthquake.
Magnitudeisdeterminedfrom
measurementsonseismograph.
INTENSITY
MEASURESTHESTRENGTHOFSHAKING
PRODUCEDBYEARTHQUAKEATACERTAIN
LOCATION.
INTENSITYISDETERMINEDFROMEFFECTS
ONPEOPLE,HUMANSTRUCTURESANDTHE
NATURALENVIRONMENT.
LAYERSOFTHEEARTH
CRUST
Crust”describestheoutermostshellofa
terrestrialplanet.Ourplanet'sthin,40-
kilometer(25-mile)deepcrust—just1%of
Earth'smass—containsallknownlifeinthe
universe.Thecrustismadeofsolidrocksand
minerals.
MANTLE
CORE
EARTHQUAKE-AND-FAULTS.pptx
EARTHQUAKE-AND-FAULTS.pptx
EARTHQUAKE-AND-FAULTS.pptx
EARTHQUAKE-AND-FAULTS.pptx

EARTHQUAKE-AND-FAULTS.pptx