Our Earth is around 4.5 billion years old. Way back in its earliest years, vast oceans dominated. There were frequent volcanic eruptions and, because there was no free oxygen in the atmosphere, there was no ozone layer. It was a dynamic and evolving planet.
Scientists know all of this – but, of course, there are still gaps in our knowledge. For instance, while we know what kind of rocks were being formed on different parts of the planet 3.5 billion years ago, we are still understanding which geological processes drove these formations.
Luckily the answers to such questions are available. Evidence is preserved in ancient volcanic and sedimentary rocks dating back to the Archaean age, between 4 billion and 2.5 billion years ago.
