Reston, VA – The U.S. Geological Survey (USGS) and the Association of American State Geologists (AASG) announced that they have developed an updated geologic time scale and color scheme for use in ...
The time scale shows the expanse of time between the Permian-Triassic mass extinction and the less severe mass extinction that wiped out the dinosaurs. Disclaimer: AAAS and EurekAlert! are not ...