This work gave rise to a process known as radiometric dating.This technique is based on a comparison between the measured amount of a naturally occurring radioactive element and its decay products, assuming a constant rate of decay – known as a half-life.He concluded that Earth was born 20 to 400 million years ago.
You’ve seen these rock layers if you’ve ever observed a cut-away section of a mountain, perhaps because a highway runs through it. In the early part of the 20th century, scientists still weren’t sure.
Radiometric dating is based upon the fact that some forms of chemical elements are radioactive, which was discovered in 1896 by Henri Becquerel and his assistants, Marie and Pierre Curie.
The discovery gave scientists a tool for dating rocks that contain radioactive elements.
Dating meteorites thus allows us to give a lower age to the Solar System (4,56 billion years old).
Lead isotope isochron that Clair Patterson used to determine the age of the solar system and Earth (Patterson, C., 1956, Age of meteorites and the earth: Geochimica et Cosmochimica Acta 10: 230-237).