Archimedes is an 83 km diameter crater located in east Imbrium basin (29.7° N, 4.0° W). Archimedes is notable for its smooth floor, but unlike other craters with smooth floors, Archimedes is flooded with mare basalt. Craters with flooded floors are geologically important as they can establish relative ages of features thanks to the geologic law of superposition.
Because both Archimedes and Imbrium basin are flooded by mare basalt, their formations must be older than the volcanic activity. Furthermore, because Archimedes is located within Imbrium basin, Archimedes must be younger than Imbrium. Just by studying relationships between features, scientists can piece together their history!
Explore more of Archimedes' floor in the NAC frame!
Go to Image Homepage