arenal-volcano.jpgWhen a volcano erupted in the Iceland some thought that these are signs of the world coming to an end. Some took the blame on the tests being done on atomic bombs. Geologists however say although Iceland is an area prone to volcanoes, volcanic eruptions happen when molten rock from the magma chamber of the earth rises up the pipe and out of the vent.

 

What is the first image that comes to one’s mind when they hear about volcanic eruption? Some think of an orange-red lava being ejected from the top of a giant and a cone-shaped mountain. The entire human community is in fear of the destructive power of a volcano.

However, to understand what causes volcanoes, a geologist Gracious Chinoda says one needs to understand earth composition. The earth has three main layers: the crust, the mantle and the core. The crust is made up of solid rock and varies in thickness. The mantle is a thick layer of molten rock (called magma), and the core is made up of an outer liquid layer.

Temperatures inside the earth are very high – over 5000’C in the core. This means that the planet on which we live is like a huge fiery ball of hot molten rock, surrounded by a few kilometers of relatively cool, hard rock – the crust. Because heat rises, the magma in the earth’s mantle has to find a way up through the crust in a similar way as hot air rising.

Recent volcanic eruptions in Iceland and its effects were felt in the airline industry as most flights were cancelled because of the volcanic cloud that engulfed Europe especially the United Kingdom.  University of Zimbabwe Geology Lecturer Dr Dennis Shoko says volcanic eruptions have various effects on areas nearer or far from the source.

 

Geologists also say Iceland is a prolific volcano area which has seen at list a third of global activity having been contributed by the area over 500 years. The area is of both plate boundary and hot spot.

Volcanic eruptions can be destructive and also lead to climate change as particles thrown into the atmosphere can hinder the sunlight from reaching the earth surface leading to low global temperatures. Geologists say the earth’s movement of a single second is the known reason that causes volcanoes.