Long period ground motion
Encyclopedia
Long period ground motion is ground movement during an earthquake
with a period
longer than 1 second
. The frequency
of such waves is 1 Hz
or lower, placing them in the infrasonic part of the audio spectrum.
Earthquake
An earthquake is the result of a sudden release of energy in the Earth's crust that creates seismic waves. The seismicity, seismism or seismic activity of an area refers to the frequency, type and size of earthquakes experienced over a period of time...
with a period
Frequency
Frequency is the number of occurrences of a repeating event per unit time. It is also referred to as temporal frequency.The period is the duration of one cycle in a repeating event, so the period is the reciprocal of the frequency...
longer than 1 second
Second
The second is a unit of measurement of time, and is the International System of Units base unit of time. It may be measured using a clock....
. The frequency
Frequency
Frequency is the number of occurrences of a repeating event per unit time. It is also referred to as temporal frequency.The period is the duration of one cycle in a repeating event, so the period is the reciprocal of the frequency...
of such waves is 1 Hz
HZ
Hz is the International Standard symbol for Hertz, the unit of frequencyHZ may also stand for:* Habitable zone, the distance from a star where a planet can maintain Earth-like life* Hamilton Zoo, in New Zealand...
or lower, placing them in the infrasonic part of the audio spectrum.
See also
- Love waveLove waveIn elastodynamics, Love waves are horizontally polarized shear waves guided by an elastic layer, which is "welded" to an elastic half space on one side while bordering a vacuum on the other side...
- S wave
- P wave
- Rayleigh waveRayleigh waveRayleigh waves are a type of surface acoustic wave that travels on solids. They are produced on the Earth by earthquakes, in which case they are also known as "ground roll", or by other sources of seismic energy such as ocean waves an explosion or even a sledgehammer impact...
- Transverse waveTransverse waveA transverse wave is a moving wave that consists of oscillations occurring perpendicular to the direction of energy transfer...
- Seismic microzonationSeismic microzonationSeismic microzonation is defined as the process of subdividing a potential seismic or earthquake prone area into zones with respect to some geological and geophysical characteristics of the sites such as ground shaking, liquefaction susceptibility, landslide and rock fall hazard, earthquake-related...