Absolute Age

1. Absolute Age • The actual age of a rock, rock layer, or fossil.

2. Abyssal Plain • A large, flat surface on the ocean floor.

3. Acid Rain • Rain that contains unhealthy amounts of acid.

4. Air • A mixture of gases that surrounds the Earth.

5. Air Mass • A large “bubble” of air that has about the same temperature and humidity throughout it.

6. Air Pollution • The presence of harmful substances in the air.

7. Air Pressure • The weight of air pushing on everything around it.

8. Altitude • Height above sea level; also called elevation.

9. Atmosphere • The layer of air that surrounds the earth. • 78% nitrogen • 20% oxygen • 2% other gases

10. Bay • An area of water that is partly surrounded by land.

11. Blizzard • A snowstorm with high winds and low temperatures.

12. Butte • A steep hill that stands alone in a flat area.

13. Carbon Dioxide – Oxygen Cycle • Process by which humans and plants exchange gases.

14. Cast • A fossil that formed when a space left by an organism was filled with minerals or grains of rock that turned into solid rock.

15. Cementing • The gluing together of rock particles to form sedimentary rock

16. Cirrus Cloud • A high feathery cloud made of ice crystals

17. Cleavage • The breaking of a mineral along a smooth, flat surface

18. Climate • Characteristics of weather over an extended time.

19. Cloud • A larger group of tiny droplets that join together in the atmosphere. • Considered a liquid.

20. Cold Front • The leading edge of a moving mass of cooler air

21. Condensation • The changing of gas or vapor into liquid. • Happens as the gas cools. • Example: outside of a drink can.

22. Conservation • The wise use and protection of natural resources

23. Constructive Forces • Processes which raise or build up the surface of the Earth. • Examples: Earthquakes, Volcanoes

24. Continental Shelf • The gently sloping underwater part of a continent

25. Continental Slope • The sharp drop at the edge of the underwater part of a continent

26. Core • The center of the Earth.

27. Crater • A bowl-shaped structure at the top of a volcano or on a planet or moon

28. Crest • The highest part of a wave

29. Crust • The thin, outer layer of the Earth.

30. Crystal • A solid material found in nature that has straight edges and flat sides or that breaks into pieces with straight edges and flat sides

31. Cumulonimbus Cloud • A huge vertical cloud that can produce a thunderstorm • Also called a thunderhead

32. Cumulus Cloud • A puffy, white cloud with a flat bottom • Also called a fair-weather cloud

33. Current (ocean) • A river of water that moves through an ocean

34. Cycle • A process that repeats itself • Examples: life cycle, water cycle, seasonal cycle.

35. Delta • A large flat area of land at the mouth of a river

36. Deposition • The process of dropping or depositing sediment in a new place.

37. Desalination • The process of removing salt from sea water to produce fresh water

38. Desert • A biome that has very little rain and few plants

39. Destructive Forces • Processes which lower the surface of the Earth.

40. Dune • A hill of sand that is deposited by the wind

41. Earthquake • A shaking of the ground caused by energy being released in the crust. • Plates sliding past each other. • Measured using a Richter Scale.

42. Elevation • The land’s height above sea level • Also called altitude

43. Energy Resources • Materials in the environment that people can use as sources of energy

44. Erosion • The process of moving sediment from one place to another.

45. Estuary • The place where a freshwater river empties into the ocean.

46. Evaporation • Liquid is converted to vapor in the air.

47. Fault • A break or place where pieces of the Earth’s crust move.

48. Flow • Movement of water.

49. Fossil • A rock containing ancient plants, parts of animals, or imprints caused by organisms pressed into them.

50. Fossil Fuels • Fuel formed from the remains of once living animals. • Natural gas, coal, and petroleum.