Earthquake Flashcards
Stress
A force that acts on rock to change its shape or volume
Tension
when two plates pull apart
compression
when two plates come together
shearing
when two plates slip past each other
normal fault
when rock in pulled apart by tension
reverse fault
when compression pushes the faults together
strike-slip fault
when shearing pushes 2 plates by each other
plateau
a large high lifted land above sea level
earthquake
a shaking and trembling the results from movement of rock beneath the earth’s surface
focus
the area beneath the earth’s surface where rock that was under stress breaks and moves
epicenter
the point directly below the focus
P waves
the first waves to arrive called primary waves that vibrate up and down
S waves
seismic waves the come secondary and vibrate side to side
surface waves
slower waves that compress and expand the ground
seismograph
an instrument that records and measures an earthquake’s seismic waves
Modified Mercalli Scale
the amount of shaking from an earthquake recorded by the peoples observasions
magnitude
a single number that geoligists assign to an earthquake based on the earthquakes size
Richter scale
the earliest magnitude scale
moment magnitude scale
an instrument that rates the total energy an earthquake releases
seismogram
the record of an earthquake’s seismic waves
Folding
we rock folds under stress but doesn’t breaks and forms anticlines and synclines
anticlines
when rock bends downward
synclines
when rock bends upward
Liquefaction
turning a solid into a liquid and bringing the substances up and with the air pipes in them they rise and the heavy stuff sinks down.
fault block mountains
formed when tension drops down relative to other blocks
