No Lava Needed You’ll find the next odd volcano in East Africa. T e Dallol crater is one of the hottest places on Earth. T e sun beats down. Heat rises through the soles of your shoes. T ere’s no oozing lava, but there’s plenty of action. Here, three plates pull apart. Each moves


in a diff erent direction. As they move, the land in between them sinks. In some places, the land has dropped 48 m below sea level. As the land sinks, magma gets closer to the


surface. It doesn’t erupt, though. Instead, it heats up water in the ground. T e water can get so hot that it boils and turns into steam. T e steam can explode. It can send rock, ash, and water flying into the air. T at’s how this giant crater formed nearly a century ago.


Mud Mess


Day after day, an odd volcano in Indonesia erupts. Yet it’s not spewing lava. It’s belching mud! This mud volcano isn’t a typical volcano. Yet, like other volcanoes, rising heat from deep inside Earth affects it. It heats up water in the ground. This water mixes with gases and dirt. It makes mud. Then this hot mud rises to Earth’s surface. Even without lava, this volcano is dangerous. Mud bubbles out. It spreads like a black fl ood. It fl ows through villages and buries homes. No one knows what started the


mud fl ow. Some scientists say it was an earthquake. Others say it could have been caused by a company drilling for oil. What’s worse, no one knows when it will stop.


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Bubbling Water Today, this crater seems like an alien world. You hear a faint popping sound. It’s the sound of water boiling deep underground. T ere, this hot water picks up salts, chemicals, minerals, and acids. T is water bubbles up into the crater. It


fills pools. You don’t want to dive in, though. T ese pools are bright green and toxic. T ey stink of sulfur. Some water evaporates in the intense heat. It leaves a crust of dried salt and minerals behind. T e salt looks like piles of new snow. It crunches under your feet. T e minerals pile up, making rocky towers. Suddenly, you hear a hiss. T at’s the sound


of toxic fumes rising from the ground. It’s a reminder, too. T is place may look amazing. Yet you might not want to stay here too long. Now your odd volcano tour is over. You’ve


zipped from Antarctica to Africa. You’ve discovered how volcanoes form and where you’re most likely to find them. Maybe some of these volcanoes surprised


you. Not all volcanoes send lava flying sky high. Some don’t spurt lava at all. Yet they all share one thing. T ey form when our planet turns up the heat.


WORDWISE core: the center of Earth


crust: the surface of Earth lava: melted rock that fl ows from a volcano magma: partly melted rock inside Earth mantle: the layer of Earth under the crust


subduction: when one tectonic plate slides under another one


tectonic plate: a giant piece of Earth’s crust and upper mantle


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