1. 7th Grade Unit 8: Natural Events that Change the Environment Lesson 2: Effects of Weathering and Erosional Deposition Vocabulary of Instruction:

2. Video: Basics of Geology

3. 1. Abrasion Refers to the grinding away of rock by rock particles carried by water, ice, wind, or gravity.

4. 2. Bioerosion The process by which animals, through drilling, grazing, and burrowing, erode hard substances such as rocks and coral reefs. Crossbedded rippled burrowed sandstone.

5. 3. Carbonation Is a form of chemical weathering where carbonate and bicarbonate ions react with minerals that contain calcium, magnesium, potassium, and sodium.

6. 4. Chemical Weathering The process that breaks down rocks through chemical changes.

7. 5. Climate General pattern of weather conditions for a region over a long period time. Moist ClimateDry Climate

8. 6. Deposition Where the agents of erosion (water, wind, animals, etc.). lay down sediments.

9. 7. Exfoliation The breaking off of thin concentric shells, sheets, scales, plates, and so on, from a rock mass; measuring less than a centimeter to several meters in thickness, the loosened rock is spalled or fragmented, peeled, or stripped.

10. 8. Gravitational Erosion Caused by gravity and involves both large scale mass wasting and smaller scale erosion. Forms of gravitational erosion include avalanche, landslide, debris flow, mudflow, and sinkhole formation.

11. 9. Hydrolysis The chemical reaction of a compound with water. Hydrolysis is an important component of soil formation, and of chemical weathering.

12. 10. Ice Wedging Wedges of ice in rocks widen and deepen cracks.

13. 11. Mass Movement Any one of several processes that causes a down slope movement of sediment, soil, and rock material.

14. 12. Mechanical Weathering The type of weathering in which rocks is physically broken into smaller pieces.

15. 13. Oxidation Is when a substance reacts with oxygen to form a type of compound known as an oxide that contains at least one oxygen atom.

16. 14. Thermal Expansion Characteristic property of most solids and liquids which causes their volume to increase when they are heated.

17. 15. Weathering Physical, chemical, or biological breakdown of rocks and minerals into smaller sized particles.