The atolls are on a common submarine platform from below the surface of the sea. North Minerva is circular in shape and has a diameter of about . There is a small sand bar around the atoll, awash at high tide, with a small entrance into the flat lagoon with a somewhat deep harbor. South Minerva is parted into The East Reef and the West Reef, both circular with a diameter of about . Remnants of shipwrecks and platforms remain on the atolls, plus functioning navigation beacons.