My Science School

Volcanic bombs

A major volcanic eruption can hurl boulders high into the air. These boulders, called volcanic bombs, can be very large. Most of the material thrown out of the erupting volcano is ash, which forms a huge cloud. Steam and sulphurous gases are also released, and these can be very dangerous to bystanders. Pumice is a kind of foamed rock that is often thrown out during an eruption. It is full of tiny holes, making it very light. It is formed when gases in molten rock are boiled off; creating foam that solidifies as it cools. 

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What is the Ring of Fire?

All around the rim of the Pacific Ocean is a circle of places of volcanic activity known as the Ring of Fire. The Ring of Fire is caused by shifts in the giant plates that make up the Earth’s crust. The Pacific plate is gradually disappearing under the surrounding continental plates, and volcanic activity marks the points where this movement is taking place. Frequent earthquakes accompany the volcanic action in the countries surrounding the Pacific. Also, ocean trenches and underwater volcanoes form around the Ring of Fire. 

Picture credit: google