2. FACTORS THAT AFFECT THE RATE OF WEATHERING Page 3

3. 1.Mineral Composition The harder the rock, the slower the rate of weathering Composition dictates hardness which determines resistance to weathering. Page 3

4. WHICH LAYER IS MORE RESISTANT TO WEATHERING? LEAST RESISTANT? A B C D

5. Which rock is most resistant to weathering?

6. Which rock is least resistant to weathering?

7. You might also see it like this…

10. Welcome to Huntington Cemetery! Step inside- IF YOU DARE- CREEPY

12. Wow! We haven’t even stepped inside and we have evidence of weathering in the gate! What process is this and is it physical or chemical?

13. We are going to look at cemetery rocks… (tombstones!) and observe the weathering that has occurred in them.

14. Since tombstones are dated we can even determine how long the weathering has occurred!

15. Here is a typical marble tombstone which used to be a very popular rock for cemeteries. What mineral largely composes the rock marble?

16. Calcite is very unstable at the earth’s surface in certain climate types. Which type in particular?

17. What weathering process causes the tombstones to “dissolve”? Is this chemical or physical? CO 2 Carbonation

18. Here is another type of tombstone. It is made up of slate.

19. Compare the two tombstones in the next picture. How do they differ in terms of the types of weathering that has occurred to each? How do they compare in appearance? Which appears more weathered?

20. MarbleSlate

21. MarbleSlate Which tombstone is older?

22. MarbleSlate This means that rocks can weather at different rates!

23. This is called “Differential Weathering” Rocks weather at different rates due to differences in mineral composition. Some minerals are more stable at the earth’s surface than others! These take longer to weather.

24. Factors Affecting Weathering Rates 2.EXPOSURE - THE LONGER Weathering takes place on the outside surface of rocks. The more _____________ that occurs Weathering Page 3

25. Factors Affecting Weathering Rates As a rock breaks into smaller pieces, the ____________ area increases, therefore the rate of weathering ___________. Which will weather Which will weather The fastest? 3.Particle Size- Weathering takes place on the outside surface of rocks. So the more _____________ that is exposed to weathering, the faster the rock will be broken down. surface area surface increases Page 3

26. Surface Area Which will weather faster, solid rock or crushed rock? Why?? Page 3 The answer and explanation on next page

27. The crushed rock of course! The large rock is tightly packed and has less surface area exposed The large rock is tightly packed and has less surface area exposed The crushed rock is loosely packed and has more exposed. The crushed rock is loosely packed and has more exposed. Page 3

28. Factors Affecting Weathering Rates 4.Climate #1 factor in weathering process #1 factor in weathering process Dictates temperature and amount of moisture Dictates temperature and amount of moisture Page 3

29. Climate- 1. Temperature: a.In warm climates ____________is the dominant type of weathering. b. In cold climates ____________ is the dominant type of weathering. 2. Precipitation : a. As precipitation increases, the amount of weathering by frost action will __________. b. As precipitation increases, the amount of chemical weathering will__________________. 3. Chemical weathering is most rapid in __________, __________ climates. chemical physical increase warm moist Page 3

30. How does climate affect weathering? Physical Weathering Works better in a cool and moist climate Works better in a cool and moist climate Chemical Weathering Works better in a hot and moist environment More water = more weathering Page 3

31. WHICH DIAGRAM IS AN ARID CLIMATE? HUMID CLIMATE? AB Humid – more rounded Arid – more angular Sharp cliffs No vegetation Rolling hills vegetation _________ Climate ________ Climate humid arid Page 3

32. WHAT KIND OF CLIMATE SUPPORTS WEATHERING? COLD →→→→→→→→→→→→→→→→→→→→→→ HOT HIGH PPT ↑ LOW PPT No Page

33. Answers to Weathering and Climate Worksheet  H Yakutsk, USSR (-12°,31cm)  F Yuma, Arizona (22°,8cm)  B Minneapolis, Minnesota (5°,67cm)  D Charleston, S. Carolina (19°,123cm)  A Middletown, Connecticut (10°,95cm)  G Anchorage, Alaska (0°,37cm)  E Monterey, California (13°,52cm)  C Belize City, Belize (25°,200cm)

34. Answers to Weathering and Climate Worksheet 1) Warm and moist. The rate of chemical weathering increases, as temperature and moisture increases 2) Moist climate with alternating periods of freezing and thawing 3) Very dry or arid climate

35. Answers to Questions 1) D 2) D 3) D 4) C 5) C Page 4 6) B 7) 7) B 8) 8) C 9) 9) A 10) 10) D 11) 11) B

36. Answers to Questions 12) D 13) D 14) D 15) A 16) D Pages 5 & 6 17) C 18) B 19) A 20) D 21) D