Lecture 8 Geology 110
Text and Images from Slide
Age of Earth
- The oldest rock found so far is gneiss resulting from metamorphism of a tonalite intrusion in northwestern Canada is 4.030 billion years old
- Sandstone in Australia contains zircon sand grains as old as 4.4 billion years - oldest mineral
- Various estimates of Earth's age range from 4.4 to 4.56 billion years, so 4.50 +0.06 billion years old