The Hadean Eon
4.56 to 3.85 billion years ago

 

Cryptic Period 4.56 billion  to 4.15 billion years ago
  • 4.5 billion:  The young earth, somewhat less massive than it is now, is struck by another planetoid roughly the size of Mars.  This glancing blow creates a ring of debris around the Earth, composed primarily of lighter crustal material from both bodies, out of which the Moon forms.
  • 4.4 to 4.3 billion:  The first rains fell into the proto-oceans, coming from the early atmosphere that had become saturated with water from in-falling comets and hydrated minerals.
  • 4.2 billion:  The oldest evidence for felsic crust, or the first continents.  These would have been small land masses that eventually accreted together as tectonic action created plate collisions.

 

Basin Groups 1-9 Period 4.15 billion to 3.95 billion years ago
  •  

 

Nectarian Period 3.95 billion to 3.85 billion years ago
  • 3.8 billion:  The oldest known rocks.

 

Early Imbrian Period 3.85 billion to 3.8 billion years ago
  •  

 

Return to Miraculum Antiquitus
Return to the Explorations Index

 

Questions, comments?  Email me!

 

 

Contents © John M. and Margo L. Dollan 2003
Other usage cited at Usage Permission Page
This Page first uploaded October 7, 2003
Most recent update for this page November 21, 2003