1. Lesson 72
Find 3 types of fossils. Cast, imprint and petrified.

2. Mr. Petersen Bonneville Junior High
Lesson 72 8th Grade
Mr. Petersen
Bonneville Junior High

3. Announcements Acuity Test will be this Tomorrow. Meet in room B-1
Portfolio 3 will be due Thursday

4. Directions
You don’t have to do a Self-Starter Assignment this week.

5. Self Starter * Don’t write this week Today’s Learning Objective and Questions
Today’s Learning Objective: Students will be able to describe and model the processes of fossil formation.
Essential Question: What makes a sedimentary rock different from a metamorphic rock?
Answer: A sedimentary rock is pieces of other rocks cemented together a metamorphic rock has been changed due to a great amount of heat and pressure.

6. 8th Grade *Glossary List [ 1]
convection-
Paleontologist-
Loam-
Minerals-
Rock-forming minerals-
Ductile-
Malleable-
Land reclamation
Permeable
Physical Change-
Chemical Change-
Petrified fossil-

7. Assignment Log * Portfolio 3
Portfolio 3 Assignment Log 1---Glossary List * Portfolio Video Points  *  Lesson Constructive Response Questions 4-- Worksheet for Lesson Rock and Mineral Identification Lab 6--Cornell Notes Lesson Matching Assignment Lesson Hopes and Dreams Assignment Lesson Worksheet Lesson Word Search Lesson 70a
11--Cornell Notes Lesson 71

8. Cornell Notes [11] Rocks are composed of minerals.
Petrified fossils form when carbon molecules are replaced one at a time by silicone molecules.
Energy form the Earth’s interior causes changes to Earth’s surface for example earthquakes and volcanoes.
Earthquakes and volcanoes transfer energy from Earth’s interior to the surface for example seismic waves transfer mechanical energy, flowing magma transfers heat and mechanical energy.

9. Cornell Notes Continued. [11]
More recently deposited rock layers are more likely to contain fossils resembling existing species than older rock layer.
Sometimes changes on the earth’s surface happens very fast like when a volcano explodes.
Sometimes changes on the earth’s surface happens very slowly like the earth’s plates only move about 1 inch a year.
The Rock Cycle shows how rocks move from being one form of rock to another (sedimentary, metamorphic and igneous).

10. Announcement
Lets take time and write 3 questions and 3 answers on the Cornell Notes.

11. Questions:

12. David Attenborough * Magic In the Rocks Part 2 * 13 Minutes
Link to Video

13. Student Read
A cast fossil is a fossil that is formed when an animal, plant, or other organism dies, its flesh decays and bones deteriorate; minerals gradually enter into the cavity, resulting in a cast.
Remember the lab we did when we made a mold with clay and pored plaster in the clay mold and let it dry. The plaster inside the mold would be the cast.

14. Cast and Mold

15. Show the students 3 fossils
Have the students identify which is a cast, and imprint or a petrified fossil.

16. Petrified Fossil * Student Read
Petrified fossils are remains of an organism which have been subjected to mineral replacement.
There are various materials which can undergo petrification and they include wood which can b replaced by chalcedony or shells with pyrite.

17. Petrified Wood

18. More Petrified Wood

19. What type of fossil is this?
It is a “CAST” fossil.

20. Imprint Fossil 1 & 2

21. Imprint fossil 3

22. Fossil Test Directions
Number your papers from 1 – 11
When you are taking the test write whether the rock is a cast, imprint, mold or petrified fossil.

23. 1

24. 2

25. 3

26. 4

27. 5

28. 6

29. 7

30. 8

31. 9

32. 10

33. 11

34. Key
Cast
Mold
Petrified wood
Petrified
Imprint