C. Many times, in the past, Arctic ice has crushed down over parts of Europe, Asia, and North America. Why has this happened? And why are layers of coal found in Antarctica?
Great mountain ranges, such as the Rockies and the Andes, have been raised. What caused these mountains to rise and new seas to invade portions of the land?
Once in the age’s past, millions of mastodons and other types of animals met sudden death. During summer months many centuries ago, vast numbers of mastodons were frozen solid. Summer plants have been found in their teeth and stomachs. The meat of mastodons dug from the frozen earth is still edible. What great catastrophe deep-froze these animals?
Geologists have developed a theory that may explain all these mysteries. Place a weight on one side of a sphere, spin it at high speed and the sphere will fly into many pieces. The great Greenland icecap and the larger icecap on Antarctica are not centered on the Poles. They cooperate to put great strain on the surface of the earth. About every 20,000 years this strain causes the thirty-mile-deep surface of the earth to slip on the molten rocks below. From time to time, points on the earth have moved as much as 2,000 miles from their previous positions. Great earthquakes, like one in Assam that raised Mount Everest more than a hundred feet, indicate that the earth’s surface may be about to move again.