In a report published in Nature Geoscience, a scientific team studying rocks in Australia, used Australian zircons in the Jack Hills that are embedded in the rocks to decide the age and history of these rocks.
They found evidence that the Earth’s crust first formed at least 4.4 billion years ago. They analyzed the atoms in zircons and used them like a clock to decide when they were formed. The clock inside the zircon is the radioactive element uranium, and over time it becomes lead. … Read more