All About Volcanoes

All About Volcanoes

Chapter 1 Mount Saint Helens In 1980, rumbles shook the ground around Mount Saint Helens, a mountain in the state of Washington. Scientists watched the mountaintop grow larger and larger. They saw cracks forming, and they knew something big was about to happen. All of a sudden there was a big BOOM! The mountaintop exploded with a roar.

The huge blast destroyed millions of trees. It flattened them like a bunch of sticks. Heat from the blast melted the snow on top of the mountain. The melted snow mixed with dust. It made a thick mud that raced down the mountainside. The mud buried houses, cars, roads, and bridges.

Early warning Months before the blast, scientists saw clues that Mount Saint Helens was about to burst. The police warned people who lived near the mountain to leave their homes. They also warned workers, reporters, and visitors to leave the area. Hundreds of lives were saved because people left before the huge blast.

Chapter 2 How a Volcano Forms Mount Saint Helens is a volcano. A volcano is an opening in the Earth through which lava, ash, and gases come out. Lava is hot, melted rock that comes from deep inside the Earth. Ash is small bits of lava and rock.

Gas gets trapped in melted rock inside the Earth. The gas escaped when a volcano explodes. Then lava and rocks shoot out. This is a little like shaking a bottle of soda and the opening it. The gas in the soda causes the liquid to bubble up over the top of the bottle.