Lava is one of the substances that a volcano produces when it erupts. It consist of a material called magma which is molyen rock that rises from the depths of the earth. The temperature of molten lava reching the Earth’s surface ranges from about 700 degree to 1200 degree celsius. Most lava is thin and fast-moving and can spread out to great distances.
When the volcano has stopped erupting and the lava has been exposed to air, It begins to cool, becoming hard and rocky on the outside while remaining soft and even liquid inside. If the sides of the volcano are steep the bottom layers of lava run off while the upper section go hard. This process causes what is known as lava tunnel.
Soil which begin its life as lava is extremey fertile. For this reason people have lived near volcanoes despite the danger of periodic eruption and the risks involved
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