Slide 1Harry Williams, Historical Geology1 Introduction: The standard geologic time scale was not developed in an organized and systematic manner. Instead, the scale took…

Slide 1 Slide 2 The Earth is 4.6 Billion years old This has been broken down into 4 major time periods (Eras). This has been broken down into 4 major time periods (Eras).…

Geologic Time Scale 1 The Earth is 4.6 Billion years old This has been broken down into 4 major time periods (Eras). The 4 Time Eras are not equal in length. The last one…

Harry Williams, Historical Geology * Introduction: The standard geologic time scale was not developed in an organized and systematic manner. Instead, the scale took shape…

Harry Williams, Historical Geology * Introduction: The standard geologic time scale was not developed in an organized and systematic manner. Instead, the scale took shape…

Geologic Time Scale Pre-Cambrian From 4.6 Billon YBP until 570 Million YBP "Shield" Regions of the world are formed Bacteria Algae and âSIMPLE" Life forms…