je osere to gba Ebun Akademi bi Obinrin Osere Todarajulo.Itokasiawon ojoibi ni Awon elebun Akademi Obinrin Osere Didarajulo 1k.. 
As with other deleologic Periods, the rock beds that define the period's start and end are well identified, but the exact dates are uncertain by several million years.. 