171. Where do most earthquakes occur
June 22, 2013
Where do most earthquakes occur?
If you could look at a map that showed the entire surface of the earth and where earthquakes occur most often, you'd see a wavy ribbon that twisted up and down as it twisted around the earth. Some parts are missed entirely; others seem to have a habit of havi...
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172. Why do volcanoes appear only in certain places
June 22, 2013
Why do volcanoes appear only in certain places?
There are no volcanoes near New York City or London or Paris-nor are there likely to be any in the future. Yet there are parts of the world where there are several volcanoes quite near each other.
Central America, bordering th...
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173. Why do we still have glaciers today
June 22, 2013
Why do we still have glaciers today?
The great ice mass that began the Ice Age in North America has been called "a continental glacier; it may have been about 4,500 metres thick in its center. This great glacier probably formed and then melted away at least four times during the Ice Age. ...
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174. When did the ice age end
June 22, 2013
When did the ice age end?
Most people think of the lee Age as something that happened so long ago that not a sign of it remains. But did you know that geologists say we are just now reaching the end of the Ice Age? And people who live in Greenland are actually still in the Ice Age as far as...
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175. How are icebergs formed
June 22, 2013
How are icebergs formed?
We may think of icebergs as exciting and interesting things to see, but they are a great danger to ocean vessels when they drift into shipping routes. One of the greatest disasters at sea took place when the Titanic struck an iceberg on the night of April 14, 1912, a...
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176. How are caves formed
June 22, 2013
How are caves formed?
Caves have long been linked with the history of man in many interesting ways. We know that late in the Old Stone Age, caves were the winter dwelling place of people who had no other shelter.
But long after man stopped using caves as homes, ancient peo...
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177. Why are there so many different kinds of rocks
June 22, 2013
Why are there so many different kinds of rocks?
Is there any boy anywhere in the world who hasn't filled up his pockets at some time with all kinds of strange rocks? The different sizes and shapes, some rough and some smooth, the different colors, some almost like precious gems, just make us...
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178. How were the mountains made
June 22, 2013
How were the mountains made?
Because mountains are so big and grand, man thinks of them as unchanging and everlasting. But geologists, the scientists who study mountains, can prove that mountains do change, and that they are not everlasting.
Certain changes in the earth's ...
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179. Why does water flow out of a spring
June 22, 2013
Why does water flow out of a spring?
All the water that flows out of every spring once fell as rain. The rain water soaks into the soil and enters into rocks through cracks. Of course, much of the rain water remains near the surface and evaporates into the air, or plants absorb it through th...
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180. What is the gulf stream
June 22, 2013
What is the gulf stream?
The Gulf Stream is an ocean current, the most famous ocean current of all. It is like a river that flows through the sea instead of on land. But the Gulf Stream is so vast that it is larger than all the rivers in the world put together!
The Gulf Stream move...
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