Etymology The Hadean was a very violent period in the history of Earth.

Geologically, the Hadean Earth would have been far more active than at any other time in its history.

The origin of Earth's oceans remains unknown oceans are believed to have formed in the Hadean period and may have been the impetus for the emergence of life.

Evolution The origin of life on Earth is not well understood, but it is known to have occurred at least 3.5 billion years ago, during the hadean or archean eons on a primordial Earth that had a substantially different environment than is found at present.