Unit 3 review

What is the primary purpose of absolute dating?

• To determine the relative age of fossils and rocks

• To determine the absolute age of fossils and rocks

• To study the order and position of rock layers

• To identify the types of fossils present

Which method uses the half-life of radiometric isotopes to determine the exact age of fossils and rocks?

• Stratigraphy

• Radiometric dating

• Fossilization

• Index fossil dating

Tags

NGSS.HS-PS1-8

What is the half-life of a radioactive isotope?

• The time it takes for all atoms in a sample to decay

Tags

NGSS.HS-PS1-8

Which isotope is commonly used for dating organic materials up to 50-60,000 years old?

• Uranium-238

• Carbon-14

• Potassium-40

• Thorium-232

What is the principle of superposition?

• Rock layers form in vertical lines unless disturbed

• Oldest rock layers are at the bottom, youngest at the top

• Rock intrusions are always older than the layers they occur in

• Rock layers are always horizontal

Tags

NGSS.MS-ESS1-4

Which principle states that rock intrusions are always younger than the layers they occur in?

• Principle of Superposition

• Principle of Original Horizontality

• Principle of Crosscutting Concepts

• Principle of Fossil Succession

What is the longest interval of time in the geologic time scale?

• Era

• Period

• Epoch

• Eon

Tags

NGSS.MS-ESS1-4

In which epoch are we currently living?

• Jurassic

• Cambrian

• Holocene

• Triassic

What is the most common type of fossilization?

• Mold and cast

• Full body fossil

• Permineralization

• Amber preservation

What is an index fossil used for?

• To determine the absolute age of rocks

• To define distinct periods of geologic time

• To study the order of rock layers

• To identify the type of rock

Tags

NGSS.MS-ESS1-4