Steven Dutch, Natural and Applied Sciences, University
of Wisconsin - Green Bay
Scale: 1 pixel = 2 km. 5-degree grid; Mercator Projection, Center 00NS 140E
|Copernican: Beginning with the formation of the
bright crater Copernicus, about 1.1 Ga. Formation of bright ray
Eratosthenian: Begins with the formation of the crater Eratosthenes. Fresh but non-rayed craters and late mare eruptions. 1.1 to 3.1 Ga.
Imbrian: Begins with the formation of the Imbrium Basin. Includes most mare eruptions. 3.1 to 3.8 Ga.
Nectarian: Begins with the formation of the Nectaris Basin, and includes most of the major impact basin events. 3.8 to 3.9 Ga.
pre-Nectarian: Before 3.9 Ga
Created 11 April 2014, Last Update
Not an official UW Green Bay site