Variations in salt and sulfate minerals detected by the Curiosity Rover in Gale Crater on Mars may indicate that areas on the crater floor underwent a series of wet and dry periods similar to some saline lakes on Earth, according to a new paper released on October 7. Preserved mud cracks in the area already indicated that it had once been wet (see image). Variations in mineral composition between stratigraphic layers and within cracks suggest they formed in pools of water that evaporated to produce brines, but then later refilled.
For more information, please visit NASA’s Curiosity Rover Finds an Ancient Oasis on Mars , or the paper by Rapin, et al. at An interval of high salinity in ancient Gale crater lake on Mars.