Describe and Account for the Relationship Between Earthquakes and Volcanic Activity
Describe and account for the relationship between earthquakes and volcanic activity
The close relationship between earthquakes and volcanic activity is evident from the maps depicting the locations which are prone to both. Volcanism is associated with two of the plate boundary types: divergent and convergent margins, so activity is usually found along oceanic ridges where plates are moving apart, near rift valleys, on subduction zones where the most violent activity takes place and over hot spots which have given rise to the Hawaiian islands. Magma is generated at most plate boundaries, and this magma rises to the surface to form volcanoes. The mobility of crust also causes earthquakes. When plates collide or slide past each other, it leads to generation and accumulation of pressure (strain) which when released causes earthquakes. The point at which this pressure releases occurs within the crust at the focus, however the shock on the surface is felt the greatest at the epicentre which is directly above it.
When comparing the maps, it is clear that the earthquake zone and the volcanic zones often overlap. Both earthquakes and volcanoes occur at the boundaries of tectonic plates, which make up the Earth's surface.
It is possible that large earthquakes can trigger local volcanoes to erupt. Stress changes caused by large earthquakes may either compress or expand nearby magma reservoirs. The compression could increase the reservoir pressure, while in the latter case; the expansion could cause tensile fractures around the reservoir. Either way, it increases the chance of eruptions following an earthquake. An example of possible triggering occurred after the 9.5 magnitude Chile earthquake on May 22, 1960. About 38 hours after the mainshock, Puyehue-Cordón Caulle in Central Chile erupted violently after being inactive for more than 25 years. In this instance it is likely that the fault rupture extended beneath the volcano. There is also clear evidence that large,
The close relationship between earthquakes and volcanic activity is evident from the maps depicting the locations which are prone to both. Volcanism is associated with two of the plate boundary types: divergent and convergent margins, so activity is usually found along oceanic ridges where plates are moving apart, near rift valleys, on subduction zones where the most violent activity takes place and over hot spots which have given rise to the Hawaiian islands. Magma is generated at most plate boundaries, and this magma rises to the surface to form volcanoes. The mobility of crust also causes earthquakes. When plates collide or slide past each other, it leads to generation and accumulation of pressure (strain) which when released causes earthquakes. The point at which this pressure releases occurs within the crust at the focus, however the shock on the surface is felt the greatest at the epicentre which is directly above it.
When comparing the maps, it is clear that the earthquake zone and the volcanic zones often overlap. Both earthquakes and volcanoes occur at the boundaries of tectonic plates, which make up the Earth's surface.
It is possible that large earthquakes can trigger local volcanoes to erupt. Stress changes caused by large earthquakes may either compress or expand nearby magma reservoirs. The compression could increase the reservoir pressure, while in the latter case; the expansion could cause tensile fractures around the reservoir. Either way, it increases the chance of eruptions following an earthquake. An example of possible triggering occurred after the 9.5 magnitude Chile earthquake on May 22, 1960. About 38 hours after the mainshock, Puyehue-Cordón Caulle in Central Chile erupted violently after being inactive for more than 25 years. In this instance it is likely that the fault rupture extended beneath the volcano. There is also clear evidence that large,