Information on the World's Most Famous Volcanoes

 

 

When learning about the dynamics of our planet, Earth, one of the most fascinating things that you will study are its volatile features and the famous volcanoes that have resulted because of them.  The field of volcanology is one of the newest and most exciting careers that young people can become involved in, as well as having great benefits to geology in general.  In order to be able to predict new activity, it is necessary to study the series of events that led to past eruptions.


Earth is a vibrant planet; one that is composed of many layers from the surface to the core.  The surface that we can visually see is the rigid outer surface layer.  This outer layer is divided into tectonic plates; eight major plates exist across the entire Earth’s surface and numerous minor ones.  These plates “float” upon the asthenosphere layer beneath the outer layer; continuously in movement upon the partially molten rock layer.   Volcanic activity is generally found at the boundaries of the tectonic plates.  Divergent boundaries mean that two plates are moving away from each other; these are often mid-oceanic ridges.  Convergent boundaries mean that two or more tectonic plates move toward each other and collide.  One other type, transform plate boundaries, occurs when plates move past one another; this type is least likely although not impossible to have volcanic activity. 


Volcanoes are openings that occur in the earth’s crust.  Magma, or molten rock, beneath the outer crust are pushed up through the fissure and out into the environment.  This molten rock is called lava when it reaches the opening and flows out.  The lava cools and hardens; forming lava rock.  When volcanoes erupt, they pose great danger to all people and wildlife that live nearby.  While the lava will certainly kill any living thing within its path, there are other dangers as well.   Toxic gasses such as sulfur dioxide are emitted into the atmosphere along with lava.  These fumes can create respiratory issues with people, especially those already suffering from breathing problems.   Ash and dust produced from the matter that is thrown into the air will remain in the environment for quite some time, wreaking havoc with air quality for breathing and visibility. 


Over time, a number of volcanoes have erupted in various areas across the world.  Some have served to be more memorable than others because of their ferocity, the affect they have had on the environment and their deadly consequences.   Some of the most famous volcanoes are:


Italy’s Mt. Vesuvius:  One of the earliest of the deadly volcanoes, Mt. Vesuvius, erupted in 79 AD, utterly destroying the cities of Pompeii and Herculaneum.  All eruptions since that time have been notably less severe; however, Mt. Vesuvius is considered to be one of the most dangerous volcanoes on earth because of the high population in the immediate vicinity. 


Indonesia’s Mt. Tambora:  At least 71,000 people died as a direct result of the eruption of Indonesia’s Mt. Tambora in 1815.  Measuring 7 on the Volcanic Explosivity Index, this was the largest recorded eruption in history.  The impact on the environment was so intense that the eruption actually created a volcanic winter; the year following is termed as “the year without a summer”, its trademark making it one of the most famous volcanoes.  Two large snowstorms were recorded in New England and eastern Canada as occurring in June, resulting in a huge loss of crops and the loss of many human lives.  Four other major volcano eruptions in 1812, 1813 and 1814 had also contributed to the vast, widespread climatic disruption which culminated in the Mt. Tambora explosion. 

Indonesia’s Krakatau:  Of the 130 active volcanoes situated in Indonesia alone, Krakatau is known for its highly explosive eruptions even though it is not counted among the largest of volcanoes.  In 1883, it displayed its venomous power through a cataclysmic explosion that caused the northern section of the island to disintegrate into the ocean, which caused massive tsunamis.  At least 36,000 people died as the huge walls of water crashed down upon them, wiping out numerous towns and villages that had previously dotted the coastline.  Some islands were completely obliterated and ceased to exist as land.   The end result was the near full destruction of the island and Krakatau itself.  So far into the atmosphere had the tephra been thrust that it would be years before all of it would dissipate.  Temperatures dropped world round as sunlight was filtered through the debris, and the sky became a canvas on which striking colorations and formations would occur for several years.

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