Briefing
Mountains, rivers, and canyons don't just spring up out of thin air. It takes millions of years to shape them. In this Mind Game, you'll get to see how that works without waiting so long!
Activity
When the game begins, you'll see two pictures.
The picture on the right is your GOAL. In other words, that's what you?re trying to make.
The picture on the left is what you're starting out with.
Across the bottom of the screen are buttons, representing different forces of nature: wind, flowing water, volcanoes, and glaciers. Click on the button that you think is needed to reach your goal.
If you pick the wrong button, we'll tell you, and you'll get another chance.
If you choose correctly, you'll get a new set of buttons to choose from. These represent different amounts of time: 100 years, 10,000 years, or 20 million years. Click on the amount of time that you think will get you closest to your goal -- without going past it!
Once you choose your time, see what you end up with. Does it match your goal? If not, try again! If it does, move on to the next challenge!
Debriefing
How did you choose which forces to use? Were you surprised by how much time it took to reach your goal? What would happen if you had even more time?
If you've got your Case Journals, go answer the questions in it now!
More Info
Volcanoes are among the most powerful forces that shape the earth. In just a few hours, a volcanic eruption can bring up tons of magma: hot liquid rock from deep below the Earth's surface. When that liquid rock erupts, it's called lava. The lava quickly cools into a black, rocky, dry surface. Over time, the hardened lava softens and becomes rich with minerals, making it possible for plants to grow. The Hawaiian Islands all began as underwater volcanoes.
Water may seem wimpy compared to volcanoes, but over time it can make a big impact. Flowing water (from rivers, rain, or melting snow) carries away rock and soil and drops it off in other places. Snow and ice also can break apart rocks by melting into cracks and then re-freezing. The Grand Canyon was mostly carved out by two forms of water: the Colorado River and melting snow.
Glaciers are big, slow-moving hunks of ice. As they melt, re-freeze, and creep across the landscape, they pick up rock, soil, and minerals, and carve intricate patterns into the Earth?s surface. Although they move far too slowly to notice with the naked eye, they can travel at speeds of up to 12 inches per year -- which means that one person could notice significant movement over the course of his or her lifetime. Glaciers are often responsible for the shapes of valleys in mountain ranges, and can leave "footprints" that include lakes, ravines, and unusual rock shapes.
Wind is a force that can shape the Earth anywhere, but its effects are most noticeable in dry places. Wind can wear away the surface of a rock over a long time. Sometimes that makes the surface of the rock look smooth and polished. Wind can also wear away the softer minerals in a rock and leave the harder ones behind, creating jagged, craggy surfaces. The effects of wind are especially strong in the desert, because the wind blows sand that helps wear away the rocks.