Faults Earthquakes begin on a fault _________ movement will not proceed smoothly away from the fault due to Changes along the _________and ________ of the fault

Amount of friction along the fault cause _______ movement –________ __________ –Strength of fault –Natural barriers to movement Direction of fault _____________ of fault surface

_________ _______ faulting Faulting in which the movement is ___________ associated with __________, are surfaces where rock bodies slide past one with _____vertical movement.

___________________ caused by ___________ forces pulling the rock ______. The result is a fault in which the ____________ _____ (upper block of rock) has moved downward relative to the ____________. ___________________ caused by _______________ forces squeezing the rock until it _________. the hanging wall will move _________relative to the footwall. Wikipedia

Stick slip: a _________ motion of fits and starts As energy builds up, the rock on either side of the fault will ______ the energy until its force _________ the ___________ of the fault

Movement along the fault will continue until the failure reaches an area where the strength of the rock is great enough to prevent further rupture Some of the energy in the rock will be released by ______________ __________ on the fault, the ___________ of the rock, the propagation of _____________ _________

Liquefaction Does _____ cause earthquakes is the result of an earthquake with a magnitude of ______ or greater Only occurs in _________ _________ sand or clay soils Vibrations cause the soil particles to ________ ________ with one another and so the soil takes on the characteristics of a ________ –AKA: quicksand or quickclay – ei=LXf6Sem8CpS6qAOxirS8Bg&q=liquefaction+earthquake&hl= enhttp://video.google.com/videoplay?docid= & ei=LXf6Sem8CpS6qAOxirS8Bg&q=liquefaction+earthquake&hl= en –

When does liquefaction occur in relation to quakes? Takes time for ________ to buildup underground Quicksand is heavy, thick fluid moves ___ Liquefaction, sand boiling and other associated phenomena are not apparent during the shaking but ________ ________ __________ = longer duration period for shaking

3 ways to induce Liquefaction 1.__________: caused by seismic waves 2.__________: caused by vibrations from trains, motor vehicles, tractors 3.__________: caused when ground water pressures increase due to rising stream levels during flooding conditions

Hyrdologically This type most commonly occurs on properties protected by levees where rivers can rise to levels above the surface Sand boils become active during river flood stages Tractors and trains etc… crossing over sand fissures during times of high water table can cause highways to sag, tracks get out of parallel and farm equipment to sink into the ground

Vocab Consolidated: tightly packed, composed of particles that are not easily separated Lifeline: a service that is vital to the life of the community. Include: transportation systems, communication systems, water supply lines, electric power lines, and petroleum or natural gas lines Liquefaction: the process in which a solid (soil) takes on the characteristics of a liquid as a result of an increase in pore pressure and a reduction in stress Sand boil: a forcible ejection of sand and water from saturated soil, caused by and earthquake or heavy flooding. Saturated: having absorbed water to the point that all the spaces between the particles are filled, and no water can enter Unconsolidated: loosely arranged, not cemented together, so particles separate easily. Ground Water: subsurface or underground water