Chapter 4 Test Flashcards
(25 cards)
a push or pull exerted on an object
Force
a measure of the amount of matter an object contains and its resistance to movement
Mass
the amount of space that matter occupies
volume
the shaking and trembling that results from movement of rock beneath Earth’s surface
earthquake
the area beneath Earth’s surface where rock that was under stress that begins to break or move
focus
seismic waves that compress and expand the ground like an accordion
p waves
the point on the surface directly above the focus
epicenter
seismic waves that can vibrate from side to side and up and down
s waves
move more slowly than p or s waves, but can produce severe ground movements
surface waves
an instrument that records and measure an earthquakes seismic waves
seismograph
a single number that geologists assign to an earthquake based on the earthquake’s size
magnitude
rates the amount of shaking from an earthquake
Modified mercalli scale
rates the magnitude of small earthquakes based on the size of the earthquake’s waves as recorded by seismographs
richter scale
rates the total energy and earthquake releases
moment magnitude scale
a force that acts on rock to change its shape or volume
stress
the stress force that pulls on the crust and thins rock in the middle
tension
the stress force that squeezes rock until it folds or breaks; 2 plates come together
compression
stress that pushes a mass of rock in 2 opposite directions
shearing
has the same structure as a normal fault, but the blocks move in a reverse direction
reverse fault
where a rock is pulled apart by tension in Earth’s crust
normal fault
the rocks on either side of the fault slip past each other
strike slip fault
a fold in rock that bend upward into an arch
anticline
a fold in rock that bends downward to form a v shape
syncline
a large area of flat land elevated high above sea level
plateau
