1. Fossils
Earth Science 11

2. How preserved…
In sedimentary rocks only, shale mostly since finer particles can preserve small details better

3. How preserved…
Actual unchanged remains – usually only bones, but rarely, soft parts too (ex if frozen)

4. How preserved…
Replaced remains – hard parts replaced by minerals in circulating solutions (ex petrified wood)

5. How preserved…
Molds and Casts – shell or bone in rock, dissolved leaving mold, other material fills in space making a cast.

6. How preserved…
Amber – hardened sap from pine trees, insects found in it (ex Jurassic Park)

7. How preserved…
Trace fossils – tracks, burrows, poop, bite marks, etc preserved

8. How preserved…
Carbonization – all the other elements disappear and a carbon imprint remains. (Typical of leaves)

9. Index fossil: Must be unique, easy to tell apart from others
Found over a wide geographic area
Was on Earth only a short time (in only a few rock layers)
If above are true, then any time you see that fossil you know how old the rock is, no matter where the rock is.

10. Fossil phyla…
Mollusca – clams (pelecypod), snails (gastropod), ammonoid, etc

11. Fossil phyla…
Brachiopod – almost extinct, similar to clams

12. Fossil phyla…
Arthropod – trilobite(extinct),
spider, crab, etc.

13. Fossil phyla…
Vertebrate – spines, people, fish, etc

14. Fossil phyla…
Plants – live on land

15. Fossil phyla…
Echinoderm – 5-fold symmetry, star fish, sand dollar, etc