Volcanic earthquakes are seismic movements that occur as a result of volcanic activity. So what is a volcanic earthquake? Does a volcanic eruption cause an earthquake?
What is a volcanic earthquake?
Volcanic earthquakes are seismic movements that occur as a result of volcanoes erupting.
What is a Volcanic Earthquake?
Volcanic earthquakes are seismic movements that occur as a result of volcanoes erupting. Molten magma deep in the Earth's crust erupts to the surface due to high pressure created by volcanic gases, causing explosions. These explosions trigger volcanic earthquakes, causing localized tremors. These types of earthquakes usually occur in areas where volcanoes are located.
Countries around the Mediterranean, Pacific and Indian Oceans are areas where volcanic activity is common. Japan and Italy in particular are among the countries known for frequent volcanic earthquakes.
Does a Volcanic Eruption Cause an Earthquake?
Volcanic eruptions can cause earthquakes, but they are generally different from tectonic earthquakes. The mechanisms by which volcanic eruptions cause earthquakes are:
1. Movement of Magma and Increase in Pressure
In volcanic areas, magma exerts great pressure on surrounding rocks as it rises through cracks in the ground. This pressure can cause rocks to fracture and cause volcanic earthquakes (volcanic tremors). These earthquakes are usually low to moderate in magnitude.
2. Sudden Pressure Release at the Time of Explosion
During a major volcanic eruption, magma rapidly ejects, creating a large void underground. This instability can cause surrounding rocks to collapse and new faults to rupture. In some cases, this can trigger powerful earthquakes.
3. Earth Collapse (Caldera Formation)
If a large eruption releases a significant amount of magma, the upper part of the volcanic edifice begins to collapse. This collapse can cause widespread ground movements, which can then produce a major earthquake. For example, large volcanic eruptions such as Krakatoa (1883) and Santorini (1600 BC) have caused such collapses and earthquakes.
4. Volcanic Eruptions Trigger Tectonic Faults
If a volcano is near a fault line, tremors from the eruption can affect that fault line and trigger a larger tectonic earthquake. The Pinatubo Eruption in 1991 triggered earthquakes along nearby fault lines.
Are Volcanic Earthquakes Occurring in Turkey?
Since there are no active volcanoes in Turkey, volcanic earthquakes are quite rare. Although there have been some volcanic movements throughout history, the probability of such earthquakes occurring in Turkey today is quite low. However, there are mountains such as Nemrut, Ağrı and Erciyes, which are known to have had volcanic activity in ancient times. However, these volcanoes are now considered extinct.
Volcanic earthquakes are events that are generally regional in effect but can affect larger areas with large explosions. Although such seismic movements are common in regions where volcanoes are active, they are very rare in regions where there is no active volcanism, such as Turkey.
