earthquakes Flashcards
ring of fire
string of volcanoes and sites of seismic activity, or earthquakes, around the edges of the Pacific Ocean.
Strike-slip fault
fracture in the rocks of Earth’s crust in which the rock masses slip past one another parallel to the strike, the intersection of a rock surface with the surface or another horizontal plane.
Normal fault
dip-slip fault in which the block above the fault has moved downward relative to the block below.
Reverse fault
dip-slip fault in which the upper block, above the fault plane, moves up and over the lower block
P-waves
waves travel fastest and are the first to arrive from the earthquake
S-waves
rock oscillates perpendicular to the direction of wave propagation.
epicenter
the location directly above it on the surface of the earth
focus
place inside Earth’s crust where an earthquake originates.
Richter magnitude scale
quantitative measure of an earthquake’s magnitude
explosive volcano
earthquake that is the result of the detonation of a nuclear and/or chemical device.
nonexplosive volcano
generally occur when magma is thin and flows easily.
Krakatoa
first indication that something was happening on Krakatoa was when a large earthquake struck the area
Yellowstone supervolcano
a massive volcano that is capable of erupting with devastating global consequences.
. San Andreas fault
represents the transform (strike-slip) boundary between two major plates of the Earth’s crust: the Northern Pacific to the south and west and the North American to the north and east.
. Mid-oceanic ridge
MID-OCEAN RIDGES AND NEARBY TRANSFORMS REFLECT THE CREATION OF THE LITHOSPHERE AS THE PLATES MOVE APART, CAUSING A RIFT VALLEY.
