Geologic History: ESRT page 8

Front

What is geologic time?

Back

Geologic time is the timeline of Earth's history, divided into eons, eras, periods, and epochs, based on significant geological and biological events.

Front

What defines the beginning and end of geologic time units?

Back

Units of geologic time are defined by major changes in life forms, such as mass extinctions or significant evolutionary developments.

Front

What is an index fossil?

Back

An index fossil is a fossil that is used to define and identify a particular time period in the geologic time scale, characterized by a narrow time frame and wide geographic distribution.

Front

Which era is known for the first appearance of fish?

Back

The Paleozoic Era is known for the first appearance of fish.

Front

What are the three periods of the Mesozoic Era?

Back

The three periods of the Mesozoic Era are the Triassic, Jurassic, and Cretaceous periods.

Front

What is the significance of the Permian period?

Back

The Permian period is significant because it ended with the largest mass extinction in Earth's history, known as the Permian-Triassic extinction event.

Front

When did the Jurassic period occur?

Back

The Jurassic period occurred approximately 201 to 145 million years ago.

Front

What major event marks the end of the Cretaceous period?

Back

The end of the Cretaceous period is marked by a mass extinction event that led to the extinction of the dinosaurs.

Front

What is the oldest period of the Mesozoic Era?

Back

The oldest period of the Mesozoic Era is the Triassic period.

Front

What is the difference between the Paleozoic and Mesozoic eras?

Back

The Paleozoic Era is characterized by the development of early life forms, including fish and amphibians, while the Mesozoic Era is known as the age of reptiles, including dinosaurs.