Fossils And Dating

Question 1

An impression, cast, original material, or track of any animal

Answer 1

Fossil

Question 2

Fossils that had a short well-known existence

Answer 2

Index fossil

Question 3

Three conditions that promote fossilization

Answer 3

Hard body parts
Rapid burial
Lack of oxygen

Question 4

What are two reasons why organisms with hard body parts are fossilized a lot easier than organisms without

Answer 4

1. Scavengers typically don’t eat bones or shells

2. Bones and shells decay much slower than soft tissue

Question 5

What are some examples of lack of oxygen environments?

Answer 5

Tar pits, ice, Amber

Question 6

What can fossils tell us about earth’s history?

Answer 6

They can tell us when life first appeared on earth, when plants and animals first lived on land, and when organisms became extinct

Question 7

What are the four types of preservation of fossils?

Answer 7

Mineral replacement
Carbon films
Coal
Trace fossils

Question 8

What is the difference between permineralization and replacement?

Answer 8

In permineralization, the pores in the tissue are filled with minerals that are found in groundwater. In replacement, all hard body parts are replaced with minerals found in groundwater

Question 9

Where is coal formed and what is it made from?

Answer 9

Coal is formed in swampy regions. It is made of carbon

Question 10

What is a trace fossil? Why are they so helpful?

Answer 10

Trace fossils are tracks, burrows, and casts. They tel you about the activity of the organisms

Question 11

Describe the six types of trace fossils…

Answer 11

Mold- outside surface of an organism
Cast- replica of the organism
Burrows- where underground animals dig dirt out
Gastroliths- stones from a bird or dino stomach
Coprolites- poop fossils
Tracks- footprints

Question 12

What did James Usher do?

Answer 12

Was the fist to try to date the earth. He used the Bible. Concluded earth was only six thousand years old.

Question 13

What did James Hutton do?

Answer 13

He was known as the father of modern geology. Developed uniformitarianism which states that the earth developed over a long period of time. He also stated that “the present is the key to the past”

Question 14

What did William Smith and George Cuvier do?

Answer 14

They developed the law of faunal succession

Question 15

What is the difference between absolute and relative dating?

Answer 15

Absolute- uses radioactive decay to determine the exact age of rocks
Relative- uses a set of laws to put rocks into proper formation

Question 16

Briefly describe the seven principles of relative dating…

Answer 16

Superposition- oldest rocks are at the bottom
Original horizontality- rocks are laid down, then folded or tilted
Cross-cutting relationships- younger cuts across older
Inclusions- rock enclosed in other rocks
Unconformity- rock has been eroded away
Faunal succession- same fossils found in different places
Contact metamorphism- metamorphic are older than sedimentary

Question 17

What are the three types of unconformities?

Answer 17

Angular
Disconformity
Nonconformity

Question 18

What are the subatomic particles of an atom called and what are their charges?

Answer 18

Protons- positive
Neutrons- no charge
Electrons- negative

Question 19

Where are the subatomic particles located?

Answer 19

Inn the nucleus

Question 20

What must be true in order for radioactive decay to occur and be accurate?

Answer 20

Must be measurable
Constant rate
Must be unidirectional(C14-N14 never the other way)

Question 21

What is the half life of carbon-14

Answer 21

5730 years

Question 22

What does carbon decay into

Answer 22

Nitrogen

Question 23

A scientist who studies fossils

Answer 23

Paleontologist

Question 24

Why do paleontologists use carbon instead of other elements?

Answer 24

Cuz it has the shortest half life