It stretches from the crater Archimedes southeast toward the rugged Montes Apenninus range located on the southeastern edge of Mare Imbrium.

[2] This region is a nearly level, lava-flooded plain bounded by the crater Autolycus and nearby highlands to the northeast and the foothills of the Montes Archimedes to the southwest.

[1] In the southern part of this area is a rille system designated Rimae Archimedes.

Just to the northwest of the Palus Putredinis midpoint is the nearly submerged crater Spurr.

[4] The basalts in this mare have been interpreted as rich in radioactive elements, but low in titanium.