A volcano is an opening in the earth's crust, through which lava, ash and gases flow. The word volcano comes from the Roman god of fire - Vulcan.
A volcano erupts when the pressure inside the earth builds up and needs to escape. Molten rock, in the mantle, heats up. The magma chamber fills up, then the magma pushes up the vent and out of the crater.
There are three main types of the volcano. One is a cinder cone another a shield or a composite. The most dangerous one is composite volcano because it erupts violently with lava and ash. A volcano can be active,dormant (sleeping) or extinct.
A volcanic eruption can be both destructive and beneficial. Falling ash is dangerous to aeroplanes, can cover buildings and make it hard to breathe. Lava flows and lahars destroy everthing in their paths. However, sometimes eruptions can creature new fertile land.
Ash,lava and gas from deep inside the earth can be very destructive and dangerous during a volcano eruption. However if we are careful we can enjoy the benfits of new land and fertile soil.
by Eleva, Iva, Kane, Max, Onosai