Earths history is divided into eons, eras, periods, and epochs. The last 30-40 years are important distinct age from the holocene epoch (where we are now- started 11700 years ago stripped biological, chemical, and physical system of the earth itself to manage itself. Scientists say an epoch follows an event asteroid that demolished dinosaurs and ended cretaceous period. Farming fertilizers and amounts of nitrogen and phosphorus in soils highest in the past 100,000 years. Aluminum production has increased by 98% since the 1950s. Concrete pervasive since ww2, primary building material. We could cover the entire planet in concrete. Plastic decay slowly and leave behind techno fossils in the geological record. Amount of plastic produced each year weighs ~ as much as all humans on earth combined. Nuclear fallout fallout from thermonuclear weapons detonated in the mid 20th century. Landfills massive deposits of disposable waste that produce new minerals and elements that end up in other places.