Search results
Results from the WOW.Com Content Network
This seismic activity is used by scientists to monitor volcanoes. [2] The earthquakes may also be related to dike intrusion and/or occur as earthquake swarms. [3] Usually they are characterised by high seismic frequency and lack the pattern of a main shock followed by a decaying aftershock distribution of fault related tectonic earthquakes. [2 ...
Volcanic earthquakes, or volcanic-tectonic earthquakes, can be caused by the movement of magma or other volcanic fluids, inducing tectonic stress that leads to earthquakes of high frequency. Lower frequency volcanic earthquakes, a result of resonation (physical oscillation from seismic waves) in cracks due to magma movement, may also be ...
A hotspot's position on the Earth's surface is independent of tectonic plate boundaries, and so hotspots may create a chain of volcanoes as the plates move above them. There are two hypotheses that attempt to explain their origins. One suggests that hotspots are due to mantle plumes that rise as thermal diapirs from the core–mantle boundary. [2]
Seismic waves generated by large earthquakes enable structure below the Earth's surface to be determined along the ray path. Seismic waves that have traveled a thousand or more kilometers (also called teleseismic waves) can be used to image large regions of Earth's mantle. They also have limited resolution, however, and only structures at least ...
On Earth, volcanoes are most often found where tectonic plates are diverging or converging, and because most of Earth's plate boundaries are underwater, most volcanoes are found underwater. For example, a mid-ocean ridge , such as the Mid-Atlantic Ridge , has volcanoes caused by divergent tectonic plates whereas the Pacific Ring of Fire has ...
Seismograph recording of harmonic tremor Four major types of seismograms, or seismic signatures. A harmonic tremor is a sustained release of seismic and infrasonic energy typically associated with the underground movement of magma, the venting of volcanic gases from magma, or both in volcanoes, and with repetitive stick-slip or other impulsive activity in non-volcanic systems.
Mantle convection is the very slow creep of Earth's solid silicate mantle as convection currents carry heat from the interior to the planet's surface. [2] [3] Mantle convection causes tectonic plates to move around the Earth's surface. [4] The Earth's lithosphere rides atop the asthenosphere, and the two form the components of the upper mantle ...
An earthquake is caused by a sudden slip on a fault. Tectonic plates are always slowly moving, but they can get stuck at their edges due to friction.When the stress on the edge of a tectonic plate overcomes the friction, there is an earthquake that releases energy in waves that travel through the Earth's crust and cause the shaking that is felt.