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Geologic Time Scale and the History of Earth

Total questions: 62

Worksheet time: 42mins

Name
Class
Date
1.

When did the first fish and amphibians appear in the fossil record?

a)

Mesozoic era

b)

Paleozoic era

c)

Cenozoic era

d)

Precambrian era

2.

When did the first bacteria evolve?

a)

Cenozoic era

b)

Mesozoic era

c)

Precambrian

d)

Paleozoic era

3.

What is the second longest time span in the geologic time scale? Examples are Paleozoic, Mesozoic, and Cenozoic.

a)

Eon

b)

Period

c)

Epoch

d)

Era

4.

What are eras divided into? Examples are Cambrian, Jurassic, Crustaceous, and Tertiary.

a)

epoch

b)

era

c)

period

d)

eon

5.

The entire history of the Earth can be divided into the Precambrian (ancient) Eon and the Phanerozoic (current) Eon. Which of the following most correctly represents the percent of Earth's history occupied by each?

a)

88% Precambrian, 12% Phanerozoic

b)

12% Precambrian, 88% Phanerozoic

c)

81% Precambrian, 19% Phanerozoic

d)

19% Precambrian, 81% Phanerozoic

6.

Which of the following best describes Earth’s very first atmosphere?

a)

helium and hydrogen gases left over from the formation of the planet

b)

carbon dioxide and water vapor from volcanic outgassing

c)

a 78%-21% nitrogen and oxygen gas mixture

d)

methane and ammonia gases from Earth's interior

7.
How old do Paleontologists believe the Earth is?
a)
2015 years old
b)
3.6 billion years old
c)
4.6 billion years old
d)
4.6 million years old
8.
What are eras divided into?
a)
eons
b)
periods
c)
epochs
d)
eras
9.

During which time span did the Earth form?

a)

Precambrian

b)

Paleozoic

c)

Mesozoic

d)

Cenozoic

10.

During which time span did the oceans form?

a)

Precambrian

b)

Paleozoic

c)

Mesozoic

d)

Cenozoic

11.

During which time span did the atmosphere form?

a)

Precambrian

b)

Paleozoic

c)

Mesozoic

d)

Cenozoic

12.

During which time span did the first life appear?

a)

Precambrian

b)

Paleozoic

c)

Mesozoic

d)

Cenozoic

13.

During which time span did cyanobacteria begin photosynthesis?

a)

Precambrian

b)

Paleozoic

c)

Mesozoic

d)

Cenozoic

14.

During which era did the first multicellular life forms appear?

a)

Precambrian

b)

Paleozoic

c)

Mesozoic

d)

Cenozoic

15.

Which era is known as "The Age of the Fishes?"

a)

Precambrian

b)

Paleozoic

c)

Mesozoic

d)

Cenozoic

16.

Which era is known as "The Age of the Dinosaurs?"

a)

Precambrian

b)

Paleozoic

c)

Mesozoic

d)

Cenozoic

17.

Which era is known as "The Age of the Mammals?"

a)

Precambrian

b)

Paleozoic

c)

Mesozoic

d)

Cenozoic

18.

During which era did Pangaea break apart?

a)

Precambrian

b)

Paleozoic

c)

Mesozoic

d)

Cenozoic

19.

During which era did the ice ages occur?

a)

Precambrian

b)

Paleozoic

c)

Mesozoic

d)

Cenozoic

20.

During which era did life first appear on land?

a)

Precambrian

b)

Paleozoic

c)

Mesozoic

d)

Cenozoic

21.

In which time period are we currently living?

a)

Precambrian Time

b)

Paleozoic Era

c)

Mesozoic Era

d)

Cenozoic Era

22.

Jellyfish are one of the oldest species on Earth. In what time period did they first appear?

a)

Precambrian

b)

Paleozoic

c)

Mesozoic

d)

Cenozoic

23.

Dinosaurs, small mammals, and birds all lived during which era?

a)

Precambrian

b)

Paleozoic

c)

Mesozoic

d)

Cenozoic

24.

Which of the following is used as evidence to construct the geologic time scale?

a)

fossils

b)

radiometric age data

c)

composition of different rock layers

d)

all of the above

25.

Iridium is an element that is common in meteors bur very rare on Earth. An iridium layer 65.5 million years old has been discovered in rock layers in many different locations all over the world. For which of the following hypotheses does this discovery provide evidence?

a)

The supercontinent Pangaea began to break apart during the Mezozoic Era.

b)

A glaciation event caused the mass extinction that marks the end of the Ordovician period.

c)

An impact event caused the mass extinction that marks the end of the Cretaceous period.

d)

The "Cambrian Explosion" that marks the evolution of complex organisms happened at the beginning of the Phanerozoic eon.

26.

When did the Earth's crust form the first continents?

a)

Precambrian

b)

Paleozoic

c)

Mesozoic

d)

Cenozoic

27.

What were the only organisms alive during the Precambrian?

a)

bacteria

b)

trilobites

c)

jellyfish

d)

humans

28.

What term means many or even most species abruptly disappear from Earth?

a)

mass extinction

b)

evolution

c)

ice age

d)

glacier

29.

Which is the correct order of eras from oldest to youngest

a)

Cenozoic, Mesozoic, Precambrian, Paleozoic

b)

Mesozoic, Cenozoic, Paleozoic, Precambrian

c)

Precambrian, Paleozoic, Cenozoic, Mesozoic

d)

Precambrian, Paleozoic, Mesozoic, Cenozoic

30.

What happened during the "Cambrian explosion"?

a)

There was a major increase in the number and diversity of invertebrate species in a short period of time.

b)

Mammals began to dominate the Earth

c)

An asteroid caused a mass extinction

31.

When the oldest rocks were formed

a)

Cenozoic

b)

Palezoic

c)

Precambrian

d)

Mesozoic

32.

"Ancient Life"

a)

Cenozoic

b)

Paleozoic

c)

Precambrian

d)

Mesozoic

33.

"Middle Life"

a)

Cenozoic

b)

Paleozoic

c)

Precambrian

d)

Mesozoic

34.

"Recent Life"

a)

Cenozoic

b)

Paleozoic

c)

Precambrian

d)

Mesozoic

35.

Which came first?

a)

oceans

b)

bacteria

c)

dinosaurs

d)

people

36.

Which came first?

a)

grass

b)

bacteria

c)

dinosaurs

d)

people

37.

Which came first?

a)

mammals

b)

fish

c)

dinosaurs

d)

birds

38.

Nebraska was once underwater.

a)

True

b)

False

39.

Nebraska was once the home to mammoths.

a)

True

b)

False

40.

What are fossils that are not the actual organism but evidence of that organism's existence.

a)

index fossils

b)

trace fossils

c)

petrified fossils

d)

original preservation

41.

During a science class, Grace and Mia were discussing how different conditions can preserve remains. Which of the following is a condition that will preserve remains?

a)

amber

b)

frozen in permafrost

c)

tar

d)

all of these are correct

42.

During a school field trip to a natural history museum, Olivia and Maya learned about ancient creatures. The guide showed them some fossilized feces and asked, "What are these called?"

a)

coprolites

b)

index fossils

c)

gastroliths

d)

amber

43.

During a school trip to a natural history museum, Emma learned about smooth stones that dinosaurs swallowed to help digestion. What are these stones called?

a)

coprolites

b)

index fossils

c)

gastroliths

d)

amber

44.

During a science class, Oliver found a piece of hardened tree sap in the school garden. What is this substance called?

a)

coprolites

b)

index fossils

c)

gastroliths

d)

amber

45.

While exploring a rocky area, Charlotte found a hollowed out impression in a rock that was the same shape as a leaf. What is this type of fossil called?

a)

cast

b)

mold

c)

trace fossil 

d)

index fossil 

46.

During a field trip, Arjun discovered a fossil that formed when a hollowed-out impression in a rock, a mold, filled with sediment and then hardened. What type of fossil did Arjun find? 

a)

cast

b)

mold

c)

trace fossil 

d)

index fossil 

47.

. Which of the following is NOT a characteristic of an index fossil?

a)

has a wide geographic range

b)

is hard to find

c)

is easily recognized

d)

existed for a short geologic time

48.

A woolly mammoth found frozen in the permafrost of Siberia is an example of... 

a)

a mold

b)

an altered hard part

c)

a cast

d)

preserved remains

49.

Luna and Ava are studying fossils in their science class. What kinds of things can they learn from fossils? Check all that apply.

a)

what organisms were alive in the past

b)

changes in climate

c)

how organisms have changed (evolved)

d)

how much soda cost in 1942

e)

when an organism went extinct

50.

Which is an example of absolute age?

a)

"This trilobite is older than that dinosaur."

b)

"That stromatolite is the absolute oldest fossil I've ever seen."

c)

"Velociraptors lived 71-75 million years ago."

d)

"The oldest sedimentary layer is on the bottom."

51.

A whale bone that originally contained 200 grams of radioactive carbon-14 now contains 25 grams of carbon-14. How many half-lives have passed since this whale was alive?

a)

1

b)

2

c)

3

d)

4

52.

If carbon-14 is heated, the length of its half-life period would

a)

increase

b)

decrease

c)

remain the same

53.

Carbon-14 can only be used to determine the age of

a)

recently living things (thousands of years old).

b)

recent rocks (thousands of years old).

c)

very old fossils (millions of years old).

d)

very old rocks (millions of years old).

54.

What happens to a carbon-14 atom that has gone through radioactive decay?

a)

It disappears.

b)

It turns into nitrogen-14

c)

It becomes soil.

d)

It flips over so the radioactive side is face-down.

55.

Which radioactive substance would probably be used in dating the recent remains of a plant found in sedimentary deposits?

a)

carbon-14

b)

rubidium-87

c)

potassium-40

d)

uranium-238

56.

Why is radioactive decay useful for determining absolute age?

a)

Radioactive substances decay at a predictable rate.

b)

All Earth materials contain the same radioactive substances.

c)

The mass of radioactive isotopes in a material is equal to the age of the material.

d)

The half-life of a radioactive substance decreases by half after a certain amount of time.

57.

The older the rock the less parent element is found in the rock.

a)

True

b)

False

58.
The length of time required for half of the radioactive atoms in a sample to decay is its...
a)
era
b)
age
c)
half-life
d)
eon
59.

What are the oldest fossils and why?

a)

B, C- because they are closest to the top

b)

A, B- because they are closest to the bottom

c)

They are all the same age- because they are all found on layer 2

d)

A, B- because they are found closest to the top

60.

Which fossil is the youngest?

a)

fossil A

b)

fossil B

c)

fossil C

d)

fossils A and B are the same age

61.

Which layer contains the youngest fossil?

a)

layer 1

b)

layer 2

c)

layer 3

d)

layer 4

62.

Which fossil is the youngest

a)

1

b)

2

c)

3

d)

4