Written By Admin on 05 November 2009 | 11/05/2009 12:03:00 PM
Types of Volcanic Eruptions
Volcanic eruptions have caused some of the worst disasters in the world. They can wipe out entire cities and kill thousands of people.
The name of volcano comes from Roman term. It derives from VULCAN which is the name of Roman fire god. Romans believed that Vulcan lived on a volcanic Italian coast. Romans called the island VULCANO.
According to scientists, volcanic eruptions are divided in to four basic groups. They are commonly known as Hawaiian, Strombolian, Vulcanian and Peleean. The term of Hawaiian eruptions are named after the volcanoes in Hawaii. These volcanic eruptions are the least violent type. They produce highly fluid lava which flows quietly. This gradually builds up a shield volcano.
Strombolian eruptions are named after Stromboli. These result from the constant release of gas from the magma. As the gas escapes, it produces tephra that piles up, turning into a cinder cone. Strombolian eruptions happen when sticky magma plugs the central vent. This makes the magmatic gas build up pressure until it blasts. The magma is turned into volcanic dust and bombs.
Vulcanian eruption which comes from the ancient Roman belief, are more violent than the strombolian eruption. Vulcanian eruption happens and brings magma which is more viscous. Vulcanian explosions are usually larger and noisier than the Strombolian eruptions.
Paleean eruptions are famous as the most violent kind of volcanic eruptions. The name of paleean comes from the eruption of Mount Pelee, Martinique in 1902. It killed almost 38 thousands people. A Peleean eruption occurs when the magmatic gas build up tremendous pressure. This causes violent explosions with glowing clouds of hot ash and dust.
Simplified from: library.thinkquest.org/03oct/01027/volcaniceruptions.html