Exploring the Geologic Time Scale

What are the four main eons of Earth's history?

• Hadean, Archean, Proterozoic, Phanerozoic

• Quaternary, Tertiary, Secondary, Primary

• Paleoarchean, Mesoproterozoic, Ediacaran, Cambrian

• Mesozoic, Paleozoic, Cenozoic, Neoproterozoic

Name the three eras of the Phanerozoic eon.

• Cenozoic, Paleozoic, Quaternary

• Paleozoic, Neoproterozoic, Mesoproterozoic

• Paleozoic, Mesozoic, Cenozoic

• Archeozoic, Neozoic, Proterozoic

What is the significance of the Cambrian period?

• The Cambrian period is known for the extinction of dinosaurs.

• The Cambrian period was characterized by the dominance of reptiles.

• The Cambrian period marked the first appearance of flowering plants.

• The Cambrian period is significant for the Cambrian Explosion, a rapid diversification of life and the emergence of most major animal phyla.

How are periods within the geologic time scale defined?

• Periods are determined by the length of time they last.

• Periods are defined by the age of the rocks.

• Periods are based solely on climate changes.

• Periods are defined by significant of timeline of geological and biological events.

What is an epoch and how does it differ from a period?

• An epoch is a type of calendar; a period is a measurement of distance.

• An epoch is a long period of time; a period is a specific event.

• An epoch refers to a historical era; a period is a moment in history.

• An epoch is a specific point in time; a period is a duration of time.

Why is the fossil record important for understanding Earth's history?

• The fossil record is primarily used for dating minerals.

• The fossil record only shows the age of rocks.

• The fossil record is crucial for understanding Earth's history as it documents the evolution of life and environmental changes.

• The fossil record is irrelevant to climate change.

What types of information can fossils provide about past environments?

• Fossils provide information about past organisms, climate conditions, and geological features of environments.

• Fossils indicate the exact dates of past events.

• Fossils provide information about current animal behavior.

• Fossils can predict future climate changes.

Explain the principle of radiometric dating.

• Radiometric dating is used to predict future geological events.

• Radiometric dating determines the age of materials by measuring the decay of radioactive isotopes.

• Radiometric dating measures the temperature of rocks.

• Radiometric dating involves counting the number of atoms in a sample.

What is the most commonly used radiometric dating method?

• Potassium-Argon dating

• Uranium-238 dating

• Carbon-14 dating

• Rubidium-Strontium dating

How does carbon dating work and what is its limit?

• Carbon dating can only be used on rocks and minerals.

• The limit of carbon dating is around 100,000 years.

• The limit of carbon dating is approximately 50,000 to 60,000 years.

• Carbon dating is effective for dating objects up to 1 million years old.