Scientists are increasingly convinced that the Earth has entered its first major new geological phase in 11,700 years
In the early 19th century, scientists started using rock strata to divide the Earth’s 4.6-billion-year history into distinct periods. By that point, they were beginning to realise that Earth was far, far older than previously thought, and were naming and organising different rock formations in an attempt to impose order on its lifespan. This gave rise to the “geologic time scale”, a dating system based on rock and fossil formations. From largest to smallest, these chapters are called eons, eras, periods, epochs and ages.
