Earth's Eras

What era are we living in?

• Mesozoic Era

• Paleozoic Era

• Precambrian Time

• Cenozoic Era

A unit of geologic time that subdivides eras

• period

• time span

Tags

NGSS.MS-ESS1-4

Scientists divided the time between Precambrian Time and the present into three units of time, or eras.

• True

• False

Tags

NGSS.MS-ESS1-4

What eon are we living in?

• Phanerozoic 

• Precambrian

• Paleozoic

• Triassic

Tags

NGSS.MS-ESS1-4

Scientists chose where units of geologic time began on major changes in ______________ at certain times.

• life forms

• events

Tags

NGSS.MS-ESS1-4

Which era is called the "era of Recent Life" because we live in it currently? It began 66 million years ago.

• PreCambrain

• Paleozoic

• Mesozoic

• Cenozoic

What era did trilobites, fishes, and other marine organisms dominate? It is known as "era of Ancient life".

• Precambrian

• Paleozoic

• Mesozoic

• Cenozoic

Tags

NGSS.MS-LS4-1

NGSS.MS-LS4-2

The geological time scale is what?

• division of Earth's history into time units based largely on the types of life-forms

• division of Earth's history into time units based largely on the types of dead things

• division of Earth's history into time units based largely on the types of rocks

• division of Earth's history into time units based largely on the types of life-forms and sea monsters

Tags

NGSS.MS-ESS1-4

What is an eon?

• longest subdivision in the geologic time scale that is based on the abundance of certain types of fossils and is subdivided into eras, periods, and epochs

• longest subdivision in the geologic time scale that is based on the abundance of certain types of rocks and is subdivided into eras, periods, and epochs

• longest subdivision in the geologic time scale that is based on the abundance of certain types of rivers and is subdivided into eras, periods, and epochs

• longest subdivision in the geologic time scale that is based on the abundance of certain types of geologic structures and is subdivided into eras, periods, and epochs

Tags

NGSS.MS-ESS1-4

What is an era?

• a mistake

• second longest division of geologic time; is subdivided into periods and is based on major worldwide changes in types of fossils

• second longest division of geologic time; is subdivided into periods and is based on regional changes in types of fossils

• third longest division of geologic time; is subdivided into periods and is based on major worldwide changes in types of rocks

Tags

NGSS.MS-ESS1-4