To date, carbonates, sulfates, chlorides have all been detected by orbital remote sensing and surface explorations by landers and rovers, although the salt mineral assemblages on Mars demonstrated differences from those on Earth. In this paper, we will give a brief review of recent observations and studies on Martian salts. On the basis of the comparison of salt sediments on Earth and Mars, we propose that potassium salts might be widespread on Martian surface and subsurface. Besides, we found a positive correlation between the GRS results of the potassium distributions on the Martian surface and the distribution of chlorides on Mars, implying the brines in the regions where the chlorides deposited may have reached the concentration for the deposition of potassium salts, and potassium salts might be prevalent in these regions.
