Week 9 Flashcards
Earthquake
Vibration of the earth produced by a rapid release of energy
Ground shaking caused by rapid movement of one block slipping past another along fractures called faults
Hypocenter (focus)
Zone within the earth where rock placement produces an earthquake
Epicenter
Location on the earths surface directly above the focus of an earthquake
Elastic rebound
Sudden release of stored strain in rocks that results in movement along a fault
Breaks and returns to original shape
Liquefaction
Transformation of a stable soil into a fluid that is often unable to support buildings or other structures
Tsunami
Japanese word for seismic air wave
Caused by displacement of crust along a mega thrust fault in a subduction zone that suddenly lifts seafloor
Seismic waves
Form of energy that travels through the lithosphere
P waves: fastest, travels by compression and expansion
S waves : side to side shear waves. slower than P. Travels only in solids
Surface waves: seismic waves that travel along the outer layer of earth
Intensity
Measure or degree of earthquake shaking at a given scale based on the amount of damage
Magnitude
Estimate of the total amount of energy released during an earthquake based on seismic records
Modified mercali intensity scale
A 12 point scale developed to evaluate earthquake intensity based on amount of damage to various structures
Richter scale
A scale of earthquake magnitude based on the amplitude of the largest seismic wave
Moment magnitude
A more precise measure of earthquake magnitude than the Richter scale derived from the amount of displacement that occurs during a fault zone
How do strike slip and dip slip faults differ ( normal and reverse)
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In what kind of plate tech tonic setting would you find a strike slip/ thrust fault
Transform
What is an earthquakes focus
Where the slippage begins
What is an earthquakes epicenter
Spot on the surface directly above the focus
Why are deep focus earthquakes concentrated in subduction zones
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2 kinds seismic body waves: how do they differ
P and S
P is primary S is secondary.
P- slinky/ compress and expand. Change the volume of intervening material
S- rope/ changes shape of material.
Is magnitude the same as intensity/ explain
Intensity: amount of ground shaking based on damage.
Magnitude: measure of ground motion and energy
3 kinds of earthquake related hazards
Liquefaction Landslides Fire Tsunami Ground shaking
What an be done to minimize the danger of each hazard
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