Workbooks • SuperScience • Map Skills
Volcanoes
Read about new tools that help tell when an eruption may happen. Then try the science investigations. Volcano Trackers!
give some warning signs before they erupt. But in the past, these signs have been hard to measure. That’s because working near volcanoes is extremely dangerous, and scientists couldn’t get close enough. Now, new technology is helping scientists study volcanoes from far away. High- tech instruments placed near cracks in the earth’s crust can sense gases that could mean magma is moving underground. Before an eruption, the crust
can rise a little, like a balloon filling with air. Scientists have placed devices on rocks to detect these movements. They’re also measuring vibrations that pulse throughout the crust during earthquakes, which are often the first sign that a volcano is coming alive. Information from these sensors
BOOM! Lava bursts high in the air before flowing in hot-red rivers down the mountain. Hot ash shoots into the atmosphere, covering an entire continent like a giant cloud. Thousands of people flee their homes toward safety. When a volcano suddenly comes to life, watch out! Scientists want to learn how to tell when an eruption may be brewing. They hope to develop better warning systems so people can be prepared for the next big boom. Volcanoes do
gives scientists a clearer picture of how volcanoes
behave. Over time, it may help them figure out which volcano could blow next.
Inside a Volcano
What gives a volcano its fiery force? Read these steps to find out. 1 Under the soil is a solid layer of rock called the crust . Under the crust is the mantle , a layer of hot, melted rock. The melted rock itself is called magma .
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2 In some places, magma rises from the mantle into the crust. It collects in a magma chamber . As more and more magma rises, the pressure builds. The pressure gets so high, the magma can crack the rock around it.
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3 The pressure pushes magma up through the central vent of a volcano.
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4 The volcano erupts! Once magma is outside the volcano, it’s called lava . The eruption may also include hot ash, rocks, and steam.
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ARCTIC OCEAN
North American Plate
Eurasian Plate
EARTH’S CRUST is broken into big pieces called tectonic plates . The red lines show the boundaries —the places where the plates touch. At some boundaries, conditions are just right for volcanoes to form.
EUROPE
NORTH AMERICA
Eurasian Plate
Juan de Fuca Plate
ASIA
Caribbean Plate
ASIA
Arabian Plate
ATLANTIC OCEAN
Philippine Plate
Paci c Plate
Indian Plate
Cocos Plate
AFRICA
EQUATOR
INDIAN OCEAN
SOUTH AMERICA
PACIFIC OCEAN
African Plate
Nazca Plate
AUSTRALIA
South American Plate
Australian Plate
Major tectonic plate Key
SOUTHERN OCEAN
Antarctic Plate
Scotia Plate
ANTARCTICA
SOURCE: U.S. Geological Survey
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SuperScience World of WOW Spark your students’ interest in science with these colorful activity books. Each one builds essential science knowledge and supports Next Generation Science Standards with colorful nonfiction articles and hands-on investigations from the editors of Scholastic Magazines+. 112 pages + stickers $8.99 GRQ-832985 Grades 1–3 GRQ-832986 Grades 4–6
Map Skills
Map Skills for Today Build geography skills and explore the world without leaving the classroom! These map-reading activity books cover everything kids need to know about maps including cardinal directions, map keys, latitude and longitude, and so much more. A must-have for your geography unit. 48 pages $4.99 GRQ-821487 Grade 1 GRQ-821489 Grade 2 GRQ-821490 Grade 3 GRQ-821491 Grade 4 GRQ-821492 Grade 5
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