EARTHQUAKE HAZARDS Flashcards
The amount of destruction associated with given amounts of ground motion depends largely on the _____ and infrastructure according to specific codes.
design and construction of buildings
During an earthquake, buildings may sway with a characteristic frequency that depends on the _____
building’s height
size
construction
underlying material
magnitude of the earthquake
_____ or ruptures may have horizontal, vertical, or combined displacements across them and may cause considerable damage.
Ground breaks
_____ are also one of the causes of the rupture of pipelines, roads and communication cables during earthquakes.
Ground breaks
_____ is the movement of material downhill.
Mass wasting
_____ occurs by a slow gradual creeping of soils and rocks downhill, but during earthquakes large volumes of rock, soil, and all that is built on it may suddenly collapse in a landslide.
Mass wasting
_____ is a process where sudden shaking of certain types of water-saturated sands and muds turns these once-solid sediments into a slurry, a substance with a liquid-like consistency
Liquefaction
when some areas were uplifted by many tens of feet, the water table recovered to a lower level relative to the land’s surface, and soon became out of reach of many water wells that had to be redrilled.
Changes in Ground Level
also known as seismic sea waves, are usually generated from submarine landslides that displace a large volume of rock and sediment on the seafloor, which in turn displaces a large amount of water
Tsunamis
may be generated by the back-and-forth motion associated with earthquakes, causing a body of water (usually lakes or bays) to rock back and forth, gaining amplitude and splashing up to higher levels than normally associated with that body of water.
Seiche waves
Deformation on the ground that marks the intersection of the fault with the earth’s surface
Ground rupture
Disruptive up, down and sideways vibration of the ground during an earthquake.
Ground shaking
Phenomenon wherein sediments, especially near bodies of water, behave like liquid similar to a quicksand.
Liquefaction
Down slope movement of rocks, solid and other debris commonly triggered by strong shaking.
Earthquake-induced landslide
Series of waves caused commonly by an earthquake under the sea.
Tsunami
Usually not felt but can be recorded by seismograph
MAGNITUDE 2.5 OR LESS
Often felt, but only causes minor damage
MAGNITUDE 2.5 TO 5.4
Slight damage to buildings
MAGNITUDE 5.5 TO 6.0
May cause major damage in populated areas
MAGNITUDE 6.1 TO 6.9
Major earthquake causing serious damage
MAGNITUDE 7.0 TO 7.9
Great earthquake that can totally destroy communities near its epicenter
MAGNITUDE 8.0 OR GREATER