Eons Quiz Study Guide

What are the three divisions of the Precambrian Eon based on radiometric dates?

Hadean, Archean, and Proterozoic Eons.

What was the time frame of the Protozoic Eon?

542 million years to 2.5 billion years.

What significant geological event characterized the Hadean Eon?

The formation of Earth.

What mineral formation is associated with extreme temperatures during Early Earth?

Komatiite.

How did the Archean atmosphere initially form?

Through outgassing with no free oxygen present at first.

What evidence indicates the presence of oxygen in early geological history?

Banded Iron Formations (BIFs).

What was the first supercontinent formed in the Proterozoic Eon?

Gondawanaland.

What is the significance of Banded Iron Formations (BIFs)?

They reflect increasing oxygen levels in the atmosphere.

When did the first multicellular organisms appear?

During the Ediacaran period, approximately 670 - 570 million years ago.

What type of geological evidence supports the occurrence of early ice ages in the Proterozoic?

Glacial Tillite.