Start Radiometric dating human history

Radiometric dating human history

Though originally a field reserved for archaeologists, physical scientists like Walker are showing that they also have crucial contributions to make.

Since the 1950s, geologists have used radioactive elements as natural "clocks" for determining numerical ages of certain types of rocks. "Forms" means the moment an igneous rock solidifies from magma, a sedimentary rock layer is deposited, or a rock heated by metamorphism cools off.

It's this resetting process that gives us the ability to date rocks that formed at different times in earth history.

Radioactive elements are unstable; they breakdown spontaneously into more stable atoms over time, a process known as radioactive decay.

All rocks and minerals contain tiny amounts of these radioactive elements.

‘Dating is absolutely crucial, it underpins everything,’ says Michael Walker.

Based at the University of Wales Trinity St David, he has devoted his career to studying the Quaternary period – the last 2.6 million years and the so-called ‘age of humans’.

Nineteenth century geologists recognized that rocks formed slowly as mountains eroded and sediments settled on the ocean floor.