Search results
Results From The WOW.Com Content Network
P wave and S wave from seismograph Velocity of seismic waves in Earth versus depth. [1] The negligible S-wave velocity in the outer core occurs because it is liquid, while in the solid inner core the S-wave velocity is non-zero. A seismic wave is a mechanical wave of acoustic energy that travels through the Earth or another planetary body.
What causes earthquakes? Earthquakes occur when the plates that make up the Earth's crust move around. These plates, called tectonic plates, can push against each other. ... Those seismic waves ...
In its most general sense, the word earthquake is used to describe any seismic event that generates seismic waves. Earthquakes can occur naturally or be induced by human activities, such as mining, fracking, and nuclear tests. The initial point of rupture is called the hypocenter or focus, while the ground level directly above it is the epicenter.
In seismology, an aftershock is a smaller earthquake that follows a larger earthquake, in the same area of the main shock, caused as the displaced crust adjusts to the effects of the main shock. Large earthquakes can have hundreds to thousands of instrumentally detectable aftershocks, which steadily decrease in magnitude and frequency according ...
Seismology (/ s aɪ z ˈ m ɒ l ə dʒ i, s aɪ s-/; from Ancient Greek σεισμός (seismós) meaning "earthquake" and -λογία (-logía) meaning "study of") is the scientific study of earthquakes (or generally, quakes) and the generation and propagation of elastic waves through planetary bodies.
Ground motion is typically caused by surface waves, which are the most destructive type of seismic waves. Ground motion is measured using a seismometer, a device that detects and records the movement of the Earth's surface. Seismometers are used by seismologists to study earthquakes and other types of ground motion.
Research on the origin of seismic noise [1] indicates that the low frequency part of the spectrum (below 1 Hz) is principally due to natural causes, chiefly ocean waves.In particular the globally observed peak between 0.1 and 0.3 Hz is clearly associated with the interaction of water waves of nearly equal frequencies but probating in opposing directions.
Earthquake swarms raise public-safety issues: first, because the end of seismic activity cannot be predicted; second, because it is uncertain whether another earthquake with a magnitude larger than those of previous shocks in the sequence will occur (the 2009 L'Aquila earthquake in Italy illustrates this, with an M W 6.3 shock following a swarm ...