Test 2

Question 1

Geologists are able to identify and separate different periods of geologic time by studying the fossil record within rock layers, using a technique called “____ ____,” which analyzes the position of rock layers to determine which ones are older or younger based on the principle of superposition.

Answer 1

Relative Dating

Question 2

___ is the action of placing one thing on or above another, especially so that they coincide

Answer 2

Superposition

Question 3

___ age refers to the age of something compared to other things, indicating only whether it is older or younger

Answer 3

Relative

Question 4

___ age is the exact numerical age of something, measured in years, providing a specific time frame for when something existed

Answer 4

Absolute

Question 5

The principle of ___ ___ states that layers of sediment are originally deposited in flat, horizontal layers parallel to the Earth’s surface

Answer 5

Original horizontality

Question 6

The principle of ___ relationships is a geological principle that states that a geological feature that cuts through another feature is younger than the feature it cuts

Answer 6

Cross-cutting

Question 7

The principle of ___ states that if a rock fragment (inclusion) is found within another rock, the inclusion must be older than the rock that contains it

Answer 7

Inclusions

Question 8

Four geologic eras in order (oldest to most recent)

Answer 8

Precambrian, Paleozoic, Mesozoic, Cenozoic (Pr, Pa, M, C)

Question 9

Four geologic eras in order (oldest to most recent)

Answer 9

Precambrian, Paleozoic, Mesozoic, Cenozoic (Pr, Pa, M, C)

Question 10

What era is the quaternary period in?

Answer 10

Cenozoic

Question 11

What era is the palaeogene period in?

Answer 11

Cenozoic

Question 12

What era is the Cretaceous period in?

Answer 12

Mesozoic

Question 13

What era is the Jurassic period in?

Answer 13

Mesozoic

Question 14

What era is the Triassic period in?

Answer 14

Mesozoic

Question 15

What era is the Permian period in?

Answer 15

Late Paleozoic

Question 16

What era is the Carboniferous period in?

Answer 16

Late palaeozoic

Question 17

What era is the Devonian period in?

Answer 17

Late palaeozoic

Question 18

What era is the Silurian period in?

Answer 18

Early palaeozoic

Question 19

What era is the Ordovician period in?

Answer 19

Early palaeozoic

Question 20

What era is the Cambrian period in?

Answer 20

Early palaeozoic

Question 21

What epoch/period was advanced civilization recorded for the first time? Hint: in the Cenozoic era + 11,700 years ago

Answer 21

Holocene

Question 22

What epoch/period was the most recent ice age? Hint: in the Cenozoic era + 2.6 million years ago

Answer 22

Pleistocene

Question 23

What epoch/period was the K-T (dinosaur) extinction? Hint: in the Mesozoic era + 65 million years ago

Answer 23

Creatceous

Question 24

What epoch/period was the Atlantic Ocean formed? Hint: in the Mesozoic era + 150 million years ago

Answer 24

Jurassic

Question 25

What epoch/period was Pangaea formed? Hint: in the Mesozoic era + 300 million years ago

Answer 25

Jurassic

Question 26

What epoch/period was the Age of Coal Forests in? Hint: In the Paleozoic Era + ~290 million years ago

Answer 26

Carboniferous

Question 27

Which epoch/period was the Age of Fishes in? Hint: in the Paleozoic Era + ~419 million years ago

Answer 27

Devonian

Question 28

What epoch/period was the Cambrian Explosion in? Hint: in the Paleozoic Era + ~485 million years ago

Answer 28

Cambrian

Question 29

During what eon was the first life? Hint: in the Precambrian Era + ~2.5 billion years ago

Answer 29

Archean

Question 30

During what epoch/period was the first “oxygenation event?” Hint: in the Precambrian Era + ~2.4 billion years ago

Answer 30

Proterozoic

Question 31

During what epoch/period is the oldest known rock from? Hint: in the Precambrian Era + ~4 billion years ago

Answer 31

Hadean

Question 32

During what epoch/period was Earth formed? Hint: in the Precambrian Era + ~4.5 billion years ago

Answer 32

Hadian

Question 33

What happens when an atom has experienced radioactive decay?

Answer 33

It transforms into a different atom, usually a more stable one

Question 34

___ is primarily used to date organic materials like fossils or wood

Answer 34

Carbon-14

Question 35

___ is used to date older rocks, like igneous rocks

Answer 35

Uranium-235

Question 36

How is uranium-235 used to date rocks?

Answer 36

By measuring the ratio of the radioactive parent isotope (uranium) to its stable daughter product (lead) as it decays over time.

Question 37

The more ___ product present, the older the rock is

Answer 37

Daughter

Question 38

How is carbon-14 used in carbon dating?

Answer 38

It is used by measuring the amount of carbon-14 remaining in an organism after it dies. Carbon-14 gradually decays at a known rate (half-life), allowing scientists to estimate how long ago the organism lived

Question 39

What is the radioactive half-life of an element?

Answer 39

The amount of time it takes for exactly half of the atoms in a sample of that element to decay into another element through radioactive emission (aka: the time it takes for the radioactivity of a sample to decrease by half)

Question 40

What equation can be used to predict what fraction of an original radioactive sample should remain in a rock after a certain number of half-lives?

Answer 40

(1/2)^n where “n” represents the number of half-lives that have passed; meaning after one half-life, half of the original sample remains, after two half-life’s, only a quarter remains, and so on

Question 41

How do you use the ratio of parent to daughter atoms in a rock to find its age, given in number of half-lives?

Answer 41

By measuring the ratio of parent to daughter atoms in a rock, and knowing the half-life of the radioactive parent isotope, you can determine the age of the rock in terms of the number of half-lives that have passed (aka: the ratio directly reflects how many half-lives have elapsed since the rock formed