Part of the Martian Geologic Timescale
No Predecessor - Prenoachian Period - Noachian Period
The Prenoachian Period is the first period of the Martian Geologic Timescale. This period begins with the formation of Mars and ends with the formation of the Hellas impact basin and the beginning of the Late Heavy Bombardment, which would consume the Noachian Mars for 300 million years. Though there is little evidence for life on Mars, and if it had existed, the Noachian would be a more likely period for it to be found in, early Martian life may have formed in the Prenoachian. However, this early life would likely have been destroyed by the bombardment to come in the Noachian. However, whether Prenoachian life survived the bombardment and was ancestral to later Martian life, Prenoachian life was destroyed in the bombardment, or if it existed at all has yet to be universally agreed upon. The Argyre Basin, crustal dichotomy, and Isidis Basin formed during this period.
The Prenoachian is not further subdivided into epochs.
Prenoachian Timescale:
Prenoachian Period - 4500-4100 MYA