Archean

archean is the second period of the earth lasting 500 million years, during this period life and continents appeared.

life
Within the first billion years of Earth's history, life appeared in the oceans. life was very simple, it had genetic material in the form of RNA. The first cell on Earth that was created was LUCA and from this cell three domains evolved: bacteria, archaea, and eukaryotes.

atmosphere
the atmosphere had already appeared in late hadean but in archean the atmosphere was richer in ingredients than before. in archean, the atmosphere consists of hydrogen, methane, ammonia and water vapor.

continents
the in archean the first continents consisted of granite. Granite was lighter than basalt. granite it broke out of the basalt crust creating continents.