You may not have thought too much about volcanoes in the past but recent eruptions around the world may have made you to think again. In this article I hope to throw some light on this very hot topic.
A volcano is an opening in the earth's surface and occurs when tectonic plates diverge or converge. These openings allow an extremely hot substance called magma along with a variety of gases and ash to pour out from inside the earth.
Volcanoes come in different shapes and sizes and are classed as dormant, extinct or active. Their form depends on the composition of lava and how much force is present at the time of eruption. These different shapes and sizes are categorized as lava domes, cinder cones, composite volcanoes and shield volcanoes.
Gases emitted from a volcano can be more dangerous than the lava itself. Debris emitted from a volcano can also contribute to acid rain, which is potentially disastrous to many life forms.
In the past volcanoes have had a big effect on life on earth. It is believed that huge volcanic eruptions called super-volcanoes resulted in what are known as volcanic winters. The effects were so powerful that evolutionary changes occurred. It is thought that a volcanic winter took place an estimated 70,000 years ago after the super eruption of Lake Toba on Sumatra island in Indonesia.
There are more than a thousand volcanoes around the world and about 20 are erupting at any one time. Many of these volcanoes occur in the regions of Hawaii, Alaska and Iceland. Indonesia is home to the world's largest concentration of active volcanoes. Volcanoes that encircle the Pacific Ocean basin are known as the "Pacific Ring of Fire".
One volcanic event that many of us learnt about at school was the eruption of Mount Vesuvius, Italy in 79 AD. The entire population of Pompeii was buried instantly. The dramatic scene was excavated hundreds of years later.
Recently the Eyjafjallajokul volcano in Iceland erupted and produced an ash cloud that drifted across the United Kingdom and Europe. Air flights were grounded due to the potential danger to jet engines. Iceland is considered one of the most active volcanic regions in the world.
I hope you have a learned some useful facts about the danger of volcanoes - and that you have not become too alarmed!
Matilda Elkberry is a freelance writer who enjoys writing about the environment. Matilda currently writes for a website about how a wood stove blower could help you heat your home more efficiently. Matilda also recommends this resource on how to use the BCG Matrix to help improve your business.
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