History of Earth Study Guide

Geologist have two ways to describe the age of a rock: age compared to another and age in number of years since the rock formed.

• relative age and absolute age
• radioactive dating and layers of rock
• sample and fossil
• law of superposition and rock dating

Geologist use the _____________ to determine the relative ages of rock layers

• igneous rocks
• clues in the rocks
• law of superposition
• fossils

The preserved remains or traces of living things are called __________?

• rocks
• fossils
• carbon dating
• rock layers

What method do geologist used to find the absolute age of rocks?

• rock layers
• radioactive dating
• law of superposition
• past events

How could a geologist match the rock layer in one area to the rock layers found in another area?

• index fossils
• layer of sandstone
• radioactive elements
• relative age

Which layer of rock is the youngest?

• A
• B
• C
• D

Which layer of rock is the oldest?

• A
• B
• C
• D

A record of the geologic events and the evolution of life forms as shown in the rock and fossil records.

• Earth's History
• Gap in Time
• Studying Rock Layers
• Geologic Time Scale

The Precambrian Time covers about _______ of Earth's History?

• 22%
• 50%
• 70%
• 90%

How did scientist develop the geologic time scale?

• studying rocks and fossils
• Ask about the Past
• Research
• Read History books