Slow Emotion, Studium Generale, Royal Academy of Art - May2010
Chapter 8 Precambrian Earth and Life History— Hadean and Archean The Precambrian lasted for 4 b.y., 88% of estimated geologic time. No rocks are known.
Determining geological ages ◊Relative age dates – placing rocks and events in their proper sequence of formation ◊Numerical dates – specifying the actual.
1955 Cesare Emiliani (1922-1995), Geochemist He used the newly established technique of investigating different isotopes of oxygen (Oxygen-18 vs. Oxygen-16).
Chapter 8 Precambrian Earth and Life History—The Archean Eon.
