William Smith, 1815 Geologic map of England, Wales, part of Scotland The Map That Changed the World.
When looking down into the Grand Canyon, we are really looking all the way back to the early history of Earth Grand Canyon Chapter 4: Geologic Time Concepts.
Geologic TimeConcepts and Principles Chapter 4 -How do we tell time in geology?...relative dating, absolute dating Absolute age dating: 4 methods: 1. Radiometric.
Top 10 Sci-fi and Fantasy Books of 2012
Geologic Time— Concepts and Principles Chapter 4.
