What are the 4 eras of the geological time?

Answer 1

There have been 4 eons of geological time.

• Hadean Eon (4576.2 - 4000 Ma)
• Archean Eon (4,000 - 2,500 Ma)
• Proterozoic Eon (2,500 - 542 Ma)
• Phanerozoic Eon (542 Ma - Now)

There have been 10 named eras of geological time.

• Eoarchean Era (4,000 - 3,600 Ma)
• Paleoarchean Era (3,600 - 3,200 Ma)
• Mesoarchean Era (3,200 - 2,800 Ma)
• Neoarchean Era (2,800 - 2,500 Ma)
• Paleoproterozoic Era (2,500 - 1,600 Ma)
• Mesoproterozoic Era (1,600 - 1,000 Ma)
• Neoproterozoic Era (1,000 - 542 Ma)
• Paleozoic Era (542 - 251 Ma)
• Mesozoic Era (251 - 65.5 Ma)
• Cenozoic Era (65.5 Ma - Now)