Part of the Chaotian Era
Titanomachean Period - Hephaestean Period - Jacobian Period
The Hephaestean Period is the third, and final, period of the Chaotian Era, and the third of the Hadean Eon. The Hephaestean begins with the collision between Theia and the proto-Earth Tellus that formed the Earth and Moon and ends at the time from which the planet's oldest known crustal materials (detrital zircons) are known. The Hephaestean saw extreme conditions, despite the earth's molten crust having already solidified. Prior to solidification, the earth was covered by a magma ocean that reached deptchs of over 120 miles. While no life yet existed during the Hephaestean, there is evidence that the Hephaestean solidification of the planetary surface allowed for the first life to evolve during the Jacobian Period that was to follow, and liquid water was likely present on the surface by the end of this period.
The Hephaestean is not further subdivided into epochs.
Hephaestean Timescale:
Hephaestean Period - 4450-4404 MYA