Forty-eight samples of green blue, yellow, orange, and red surficial salts and efflorescences were collected at widely scattered localities in the southern half of the Heritage Range of the Ellsworth Mountains. Green and blue salts include azurite, chalcanthite, malachite, paratacamite, and malachite-paratacamite mixtures. Yellow and orange salts include alunogen, fibroferrite, an aragonite-natrojarosite mixture, natrojarosite-gypsum mixtures (± quartz), and an anglesite-beaverite mixture. All red salts are hematite-quartz mixtures (± muscovite, ± calcite). All salts form by the oxidation of pyrite, chalcopyrite, or galena and then are preserved by the cold, arid Antarctic climate. The assemblage of copper salts is different from that recently described from the Orville Coast (atacamite, antlerite, brochantite, plancheite) 500 km to the northeast. The difference in copper salts found at these two localities, coupled with studies of marine-derived Antarctic aerosols, suggests that malachite, azurite, and chalcanthite will be the common secondary copper minerals found deeper in the Antarctic interior and that copper chloride compounds will become less abundant farther away from the coast. This is the second reported occurrence of fibroferrite and the first reported occurrence of alunogen, anglesite, beaverite, chalcanthite, and paratacamite from Antarctica.

Recent orbital and rover missions to Mars have returned high-resolution images that show complex surface landforms in unprecedented detail. In addition, the spectral data sets from mission instruments reveal the presence of a wide array of mineral species on the surface of Mars. These discoveries are changing the analog science requirements of projects targeting exploration missions to Mars. Mission managers now expect field deployments to include complementary investigations of surface processes, rock types, mineral species, and microbial habitats. Earth-based analog sites are selected according to their potential for integrated geological and biological studies, wherein a central theme is the search for life. Geological field studies on Axel Heiberg Island, in the Canadian Arctic, demonstrate that the Isachsen Formation represents a high-fidelity analog for comparative studies of volcanic terrain on Mars. The two sites of interest are located in structurally complex zones (chaotic terrain) where basaltic lava flows, mafic dikes, and sandstone beds of Early Cretaceous age intersect evaporite outliers at the periphery of the diapirs. At the North Agate Fiord diapir and Junction diapir, remnant blocks of basaltic rock are pervasively altered and contain copper and iron sulfides, as well as the secondary sulfates copiapite, fibroferrite, and jarosite (North Agate Fiord diapir). Alteration zones within poorly consolidated quartzitic sandstone consist of thin layers of goethite, hematite, illite, and jarosite. The sites are morphologically different from Martian patera, but they provide access to volcanic successions and evaporites in areas of permafrost, i.e., conditions that are invoked in conceptual models for hydrothermal systems and groundwater flow on Mars.