Changes to Earth's

1. Changes to Earth's Surfaces

2. Weathering

3. Weathering is the breakingdown of rocks and other materials on the earth’s surface

4. In other words,Weathering is when rocks are broken into soil, sand, and sediment (tiny pieces or particles).

5. Weathering involves two processes that often work together to decompose or break down rocks.

6. What are 2 Types of Weathering?

7. Chemical & MechanicalWeathering

8. Chemical weathering, or decomposition, takes place when some of the rock’s minerals are changed into different substances.

9. Chemical processes that cause weathering • Acid dissolves minerals in rocks (examples: carbonic acid, acid rain and plant acid) • Acid rain can weaken rocks, corrode metal and even kill trees. • Oxygen combines with iron minerals and sulfur minerals changing the composition of the rock and forming rust. This is called oxidation. • Dissolution- Soluble compounds such as limestone are dissolved. This often forms caves.

10. Chemical processes that cause weathering • Acid dissolves minerals in rocks (examples: carbonic acid, acid rain and plant acid) • Acid rain can weaken rocks, corrode metal and even kill trees. • Oxygen combines with iron minerals and sulfur minerals changing the composition of the rock and forming rust. This is called oxidation. • Dissolution- Soluble compounds such as limestone are dissolved. This often forms caves.

11. Plant acid?

12. Lichens such as these growing on the rocks in the picture can produce weak acids that react with the rock.

13. Chemical processes that cause weathering • Acid dissolves minerals in rocks (examples: carbonic acid, acid rain and plant acid) • Acid rain can weaken rocks, corrode metal and even kill trees. • Oxygen combines with iron minerals and sulfur minerals changing the composition of the rock and forming rust. This is called oxidation. • Dissolution- Soluble compounds such as limestone are dissolved. This often forms caves.

14. Acid rain…what is the cause?

15. How acid rain forms…

17. What causes it?

22. What are the effects?

26. 1908 to 1969 Acid rain has eaten away this limestone statue. Acid Rain

27. 3000 year old Egyptian Obelisk after 100 years in NY 3000 year old Egyptian Obelisk

30. http://www.epa.gov/acidrain/education/site_students/acid_anim.htmlhttp://www.epa.gov/acidrain/education/site_students/acid_anim.html

31. Chemical processes that cause weathering • Acid dissolves minerals in rocks (examples: carbonic acid, acid rain and plant acid) • Acid rain can weaken rocks, corrode metal and even kill trees. • Oxygen combines with iron minerals and sulfur minerals changing the composition of the rock and forming rust. This is called oxidation. • Dissolution- Soluble compounds such as limestone are dissolved. This often forms caves.

32. Oxidation…what is it?

33. Oxidation reactions involve a increase in oxidation state--in other words, the transfer of electrons from a compound that is oxidized to the compound that oxidizes it. Oxygen gas is a major component of Earth's atmosphere and is fairly reactive--so much so, in fact, that it's good at combining with metals and compounds in minerals, oxidizing or "rusting" them.

34. Huh??

35. the interaction between oxygen molecules and all the different substances they may contact

36. Oxidization Oxidation turned these rocks in Nevada's Valley of Fire red.

41. Chemical processes that cause weathering • Acid dissolves minerals in rocks (examples: carbonic acid, acid rain and plant acid) • Acid rain can weaken rocks, corrode metal and even kill trees. • Oxygen combines with iron minerals and sulfur minerals changing the composition of the rock and forming rust. This is called oxidation. • Dissolution- Soluble compounds such as limestone are dissolved. This often forms caves.

42. Dissolution-forming caves?

43. Easy answer…when rain water seeps into the ground and dissolves the limestone underneath.

47. Linville Caverns, North Carolina