• Question: what makes volcans explode?

    Asked by puggy1 to Adam, Joanna, Louise S, Louise W, Marcus on 20 Nov 2012.
    • Photo: Marcus Wilson

      Marcus Wilson answered on 20 Nov 2012:

      lots of volcanoes dont explode, they just keep bubbling away spewing out small streams of lava.

      Im not really sure what it is that makes a volcano erupt. I think its the movement of magma below the earths crust, which is very hard to predict. the magma is super hot and constanly flowing, with agma at the center of the earth being hotter. but like hot water in a bath in diffuses and flows to seread out the heat, sometimes the currents pressurised towards the surface and ushes up to the volcano. an eruption happns when the force cant be relaesed, so it builds up and then explodes through a rock layer.

      usually theres earthquakes before the eruption to signal that pressure is building up.

    • Photo: Adam Paige

      Adam Paige answered on 20 Nov 2012:

      One of the deadliest parts of an exploding volcano is not the molten lava that flows down from it, nor is it the big rocks that come flying out in the explosion. Instead it is the volcanic ash that is thrown out as a volcano explodes. The ash spreads out far from the volcano as it is so light, and then slowly sinks down as a huge cloud that covers large areas of land around the volcano. If you breathe in the ash it gets into your lungs where it mixes with the mucus and water there and becomes like cement. Slowly your lungs fill up with this ash until there is not enough lung left working to deliver oxygen to your blood and you die. It is very difficult to shelter from it because it is all throughout the air. This is what killed so many of the townspeople in Pompeii in Italy many hundreds of years ago.

      One other interesting thing about volcanoes. If you live near a volcano (when it is not erupting) you are likely still breathing in very small amounts of volcanic dust. Although not as bad as the ash you get in an eruption it still contains particles of silica which can damage lung tissue. It can result in a lung disease that I heard about when I was a child because it has such a long name…

      PNEUMONOULTRAMICROSCOPICSILICOVOLCANOCONIOSIS. Try saying that fast!

Comments