There was a heaviness in the air and the animals appeared unusually restless on the farm. Santiago wondered what was wrong. And then he felt it – a small tremor as the earth seemed to shift below him. Afraid, he looked towards the Maipo Volcano that he could see in the distance. He could see smoke rising from the vents and as he listened carefully, the earth rumbled. It was about to happen — the phenomenon that he had often heard about but never seen. Soon, hot, semi liquid rock, ash and gases, called magma, would escape from the top and Maipo would erupt.
Although all continents have volcanoes, about three-quarters of them lie along the west coast of America and across the Pacific Ocean covering Japan and the islands and nations of the Pacific.
This terrifying and yet fascinating occurrence is caused in two ways. Often, it happens when the flat pieces of the rigid, crusty outer layer of the earth bump into each other with some force. (They are always moving and shifting but sometimes more powerfully than usual.) One plate plunges deep below the other causing an increase in temperature and pressure and first releasing water from the rocks and then releasing the hot fluid from within the earth’s crust or lower layers.
This fluid works its way to the surface as magma that flows from the top of the dormant volcano. At other times, there are hotspots of magmatic activity in the middle of tectonic plates that push themselves to the surface to form a volcano.
The worst eruption that we know of was in Indonesia in 1815 when Mount Tabora erupted. The explosion created a crater of about 3600 feet deep and killed approximately 10,000 people. Volcanoes are not all bad though. Volcanoes have created about 80 per cent of the earth’s surface, creating deep ravines as well as mountains. In time, the soil thereabouts becomes extremely fertile and civilisations flourish there.
The biggest problem with a volcanic eruption is that there is often little warning and the lava with its scorching rock, ash and poisonous gases race down slopes at unbelievably high speeds destroying everything in its path. This is how the towns of Pompeii and Herculaneum were wiped out in 79AD. Pompeii is, today, a world heritage site. The city was buried under almost 20 feet of volcanic ash destroying all life.
In a chilling twist, the city was preserved intact under the ashes almost as if the entire place was playing ‘statues’ for eternity. Another interesting but much more pleasant volcanic site is the Ngorongora crater in Tanzania.
A large volcanic eruption led to the collapse of the mouth of the volcano here and formed a huge bowl.
Inside this bowl thrives a fabulous ecosystem of wild animals, birds and vegetation. Most of the animals cannot get out of the bowl so it’s a safari wonderland for animal lovers all round the year.
(The author is a writer and soft-skills and communications trainer)