Numerous small mounds having summit craters are found in various locations on Mars. The mounds shown here are east of the Hellas basin. These features have been interpreted to be pseudocraters created by localized phreatic explosions where lava interacts with volatile-rich ground. Most of the mounds are between 400 meters (1,312 feet) to 1 kilometer (.62 miles) across. Many have slotlike summit vents. However, images presently available do not have sufficient resolution to show conclusive evidence of a volcanic origin for the mounds.
This image is Copyright © by Calvin J. Hamilton. Any commercial/for-profit use of this image needs to be addressed to Calvin J. Hamilton. Caption by LPI.