| A | B |
|---|
| oil | liquid produced from organic matter under pressure for millions of years |
| natural gas | a gaseous fossil fuel produced from organic matter that is used to cook and heat homes |
| pressure | exerting a force or pressing |
| sedimentary rock | rock layers formed over millions of years |
| fossil fuels | fuels formed over millions of years from the bodies of organisms that were once living |
| organic matter | made from plant or organic material |
| landform | a feature of the Earth |
| delta | where Earth materials are deposited when a river enters an ocean |
| canyon | a narrow opening in the Earth created by the movement of wind and water |
| sand dune | a large pile of deposited sand moved by wind |
| alternative energy | a source of renewable energy such as solar, wind, or geothermal |
| wind energy | energy that comes form harnessing the movement of air |
| solar energy | energy that comes from the sun |
| biofuel | fuel from plant material |
| fossil | the preserved remains or trace of an organism |
| model | a representation of something in nature |
| weather | the daily environmental conditions |
| climate | the average and overall pattern of weather conditions |
| oceans | bodies of salt water that cover 3/4 of Earth's surface |
| beach erosion | the removal of beach materials into the sea or lake by wind, waves, or tides |
| waves | moving ridges of water on the surface of the ocean caused by wind |
| rotation | spinning around a central axis |
| axis | the tilted imaginary line on which the Earth rotates |
| day | time during the 24 hours in which one side of the Earth is facing the sun |
| night | time during the 24 hours in which the sun is not visible because the Earth is facing away from it |
| moon | a natural satellite that orbits a planet |
| orbit | the path one object takes as it revolves around another object in space |
| craters | bowl shaped structures on the surface of the moon caused by meteor impacts |
| weight | the heaviness of an object affected by gravity |
| gravity | a natural force of attraction between objects, the pull of the Earth or Moon on other objects close to it |
