Science, Maths & Technology
Rock Clocks
...history of the climate from clues left in the rocks...[An unsual cliff formation] Our Earth is about 4.5 billion years old. The rock record or ‘geological time’ extends back to 4 billion years ago. Of course it cannot go back right to the formation of Earth, because the young Earth was hot and most of the outer part was probably molten, but even so this is a vast...