1. Notes Science Fossils What Are Fossils?
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Fossils
Science
What Are Fossils?
Fossils are the preserved physical remains of deceased organisms that are at least 10,000 years old
NOTE: Most organisms DO NOT become fossils after death
NOTE: The formation of fossils is a RARE event
How Are Fossils Formed?
Watch this amusing video: Link: Video: How Fossils Are Made
Primate Fossil:
47 million years old
Whale Fossil:
25 million years old

2. 8 Types of Fossils Notes Science Fossils A) Fossils In Rocks
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Fossils
Science
8 Types of Fossils
A) Fossils In Rocks
E) Frozen Fossils
B) Fossils In Amber
F) Trace Fossils
C) Petrified Fossils
G) Mold/Cast Fossils
D) Fossils In Asphalt
H) Index Fossils

3. Notes Science Fossils A) Fossils In Rocks Found in sedimentary rock
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Fossils
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A) Fossils In Rocks
Found in sedimentary rock
An organism died –was covered with mud, dirt, sand, ash, etc.
Later the mud, dirt, sand, or ash became sedimentary rock

4. Notes Science Fossils B) Fossils In Amber
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Fossils
Science
B) Fossils In Amber
Tree sap fell on a small organism, enclosed it, killed it
Over time the sap hardened into amber
The amber became covered with mud, dirt, sand, ash, etc.
Example:
Insects In Amber

5. Notes Science Fossils C) Petrified Fossils
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Fossils
Science
C) Petrified Fossils
Organism died- then was covered with mud, dirt, sand, ash, etc.
The structure of the organism was replaced with minerals
(Also known as petrifaction)
Sometimes when wood is buried, groundwater will flow through the sediment and deposit minerals in the cells of the wood.
The wood rots away & the minerals remain in the shape of the tree.
Example:
Petrified Wood
Example:
Petrified Wood

6. Saber Tooth Tiger Fossil (From La Brea Tar Pits, California)
Notes
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Fossils
Science
D) Fossils In Asphalt
Animals fell into tar pits, were trapped, and died
The asphalt hardened preserving skeletons, shells, teeth, etc.
Saber Tooth Tiger Fossil
(From La Brea Tar Pits, California)

7. Notes Science Fossils E) Frozen Fossils
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Fossils
Science
E) Frozen Fossils
Animals died in a cold climate region and were frozen
The cold temperatures preserved both soft and hard parts
Many mammoths became frozen during the last ice age
Frozen Baby Mammoth
(From Siberia, Russia)
Approx. 42,000 yrs old
Frozen Baby Mammoth
(From Siberia, Russia)
Approx: 40, 000 yrs old

8. Trace Fossil Dinosaur footprints
Notes
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Fossils
Science
F) Trace Fossils
Are impressions or “traces” left by plants and animals
Can be simple tunnels or burrows in the mud
Can be footprints or imprints in the mud etc.
(Also called ichnofossils)
Trace Fossil Dinosaur footprints
Trace Fossil
Imprint Of A Fish

9. Notes Science Fossils G) Mold/Cast Fossils
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Fossils
Science
G) Mold/Cast Fossils
In sediment, ground water may dissolve shells, leaving a shape called a mold
Sometimes the shell dissolves and is replaced by minerals, leaving behind a mineral cast of the fossil
Mold Fossil
Cast Fossil

10. …we call these index fossils
Notes
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Fossils
Science
H) Index Fossils
A way to relatively date rocks
Some fossils are commonly found at certain strata levels across large geographic areas
(A.K.A. relative dating)
…we call these index fossils
Example:
Trilobite fossils
Example:
Ammonite fossils