Due
to less active volcanoes, the Earth’s crust has begun to form.
Most of the water vapor that made up almost the entire atmosphere during
the Hadean Eon has condensed into a global ocean.
The lava, which covered most of the Earth during the previous Eon, has
now cooled to form the ocean floor. Other,
less active, volcanoes erupt to form small chains of islands in the vast ocean.
These islands are the only land surface, considering that the continents
that we know today have not formed. Every
so often, a few islands may collide and form larger islands in their places.
Since fewer asteroids hit Earth, these islands stay intact and become the
cores of our modern day continents.
The Archean eon, which preceded the Proterozoic eon, spanned about 1.5 billion years and is subdivided into four eras: the Neoarchean (2.8 to 2.5 billion years ago)
