1. MOUNTAINS

2. There are four main types of mountains.

3. Each type forms in a different way and produces mountains that vary greatly in size.

4. FAULT-BLOCK MOUNTAINS

5. The Sierra Nevada Mountains in California

7. The Teton Range in Wyoming

9. These are sharp, jagged mountains

10. They form because of pulling forces (tension)

11. Huge, tilted blocks of rock are separated from surrounding rock by faults to form these mountains.

12. FOLDED MOUNTAINS

13. The Appalachian Mountains in North America

15. They form because of colliding forces (compression).

16. Rock layers are pushed together and fold over to form these mountains.

17. UPWARPED MOUNTAINS

18. The Adirondack Mountains in New York

20. The Rocky Mountains in Colorado

22. The Black Hills in South Dakota

23. They form when forces inside Earth push up on the crust

24. VOLCANIC MOUNTAINS

25. Mount St. Helens in Washington

27. Mount Popocateptl in Mexico

29. They form when magma is forced upward and flows onto Earth’s surface

30. They can form underwater or on land

31. ISOSTASY

32. Isostasy is the principle that states that Earth’s crust and lithosphere float on the upper part of the mantle.

33. This is believed to be the force that keeps mountains elevated above the surrounding land.