earthquake Flashcards
ring of fire
The Ring of Fire is a region around much of the rim of the Pacific Ocean where many volcanic eruptions and earthquakes occur. The Ring of Fire is a horseshoe-shaped belt about 40,000 km long and up to about 500 km wide.
strike slip fault
strike-slip fault, also called transcurrent fault, wrench fault, or lateral fault, in geology, a 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
normal fault - a dip-slip fault in which the block above the fault has moved downward relative to the block below. This type of faulting occurs in response to extension and is often observed in the Western United States Basin and Range Province and along oceanic ridge systems.
reverse fault
a geological fault in which the hanging wall appears to have been pushed up along the footwall.
p-waves
A P wave is one of the two main types of elastic body waves, called seismic waves in seismology. P waves travel faster than other seismic waves and hence are the first signal from an earthquake to arrive at any affected location or at a seismograph. P waves may be transmitted through gases, liquids, or solids.
s-waves
In seismology and other areas involving elastic waves, S waves, secondary waves, or shear waves are a type of elastic wave and are one of the two main types of elastic body waves, so named because they move through the body of an object, unlike surface waves.
epicenter
The epicenter is the point on the earth’s surface vertically above the hypocenter (or focus), point in the crust where a seismic rupture begins.
focus
The focus is the place inside Earth’s crust where an earthquake originates. The point on the Earth’s surface directly above the focus is the epicenter. When energy is released at the focus, seismic waves travel outward from that point in all directions.
Richter magnitude scale
The Richter scale – also called the Richter magnitude scale and Richter’s magnitude scale – is a measure of the strength of earthquakes, developed by Charles Francis Richter and presented in his landmark 1935 paper, where he called it the “magnitude scale”
explosive volcano
In volcanology, an explosive eruption is a volcanic eruption of the most violent type. A notable example is the 1980 eruption of Mount St. Helens.
nonexplosive volcano
Nonexplosive eruptions are the most common type of volcanic eruptions. These eruptions produce relatively calm flows of lava in huge amounts. B. Vast areas of the Earth’s surface, including much of the sea floor and the Northwestern United States, are covered with lava form nonexplosive eruptions.
Krakatoa
Krakatoa, also transcribed Krakatau, is a caldera in the Sunda Strait between the islands of Java and Sumatra in the Indonesian province of Lampung. The caldera is part of a volcanic island group comprising four islands.
Yellowstone supervolcano
The Yellowstone Caldera, sometimes referred to as the Yellowstone Supervolcano, is a volcanic caldera and supervolcano in Yellowstone National Park in the Western United States. The caldera and most of the park are located in the northwest corner of Wyoming.
San Andreas fault
The San Andreas Fault is a continental transform fault that extends roughly 1,200 kilometers through California. It forms the tectonic boundary between the Pacific Plate and the North American Plate, and its motion is right-lateral strike-slip
Mid-oceanic ridge
The mid-ocean ridge is a continuous range of undersea volcanic mountains that encircles the globe almost entirely underwater. … It formed and evolves as a result of spreading in Earth’s lithosphere—the crust and upper mantle—at the divergent boundaries between tectonic plates.
