Minerals like alunite and kaolin-bearing sediments have been detected in this crater. The mineralogy inside Cross is different from other surrounding terrains and Martian basins. Waters in Cross were likely supplied by regionally upwelling groundwaters as well as through an inlet valley.
Cross Crater, about 65 kilometers in diameter, is located in the highlands of the Terra Sirenum region of Mars.
Image: NASA/JPL/University of Arizona https://www.uahirise.org/hipod/ESP_016320_1490