The beginning and end of each chunk of time in the geologic time scale is determined by when some species appeared or disappeared from the fossil record. When many species went extinct around the same ...

- Understanding the geologic time scale and how to organize Earth’s history into a coherent timeline. MS-LS4-1: Analyze and interpret data for patterns in the fossil record that document the existence ...

The Interactive Geology Project was formed in 2002 by Professor Paul Weimer and colleagues to animate Colorado’s geologic history and explore new ways of using 3D technology in earth science education ...

The Geologic Time Scale-- all 4.56 billion years of it -- is the way Earth scientists converse about time. It started off based on the relative occurrence of fossils and the periods were named after ...

Understanding the geologic time scale and how to organize Earth’s history into a coherent timeline. MS-LS4-1: Analyze and interpret data for patterns in the fossil record that document the existence, ...