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Objectives • Native Elements • Oxides • Hydroxides • Halides • Carbonates • Sulfates • Phosphates (Mg,Fe)O, a possible phase in Earth’s mantle FeO, a possible component of Earth’s core 0 FP Ca-PV Mg,Fe,Al-PV 80 95 100% Dzeiwonski & Anderson 1981 Fei & Bertka 1999 Life on Mars? hematite & olivine Goethite - Fe(OH)3 Quic kT ime™ and a T IFF (Uncompress ed) decompress or are needed to s ee this pi cture. Johann Wolfgang Goethe, 1749-1832 A German polymath: poet, novelist, scientist, painter, etc. The Sorrows of Young Werther Gibbsite - Al(OH)3 George Gibbs, 1776-1833 An American mineralogist, who donated a collection of 12,000 specimens to Yale University Carbonate minerals are useful • Carbonates cover 7% land surface • Greater than 50% oil and gas reservoirs worldwide are contained in carbonate rocks • Major economic importance as industrial "mineral" (agriculture stone, cement) Carbonates are born, not made Coral reef Stromatolites living fossils Pacific reef Red Sea reef Florida reef Caribbean reef Carbonate cavern Stalactites & Stalagmites, NM, USA Sinkholes Winter Park, Florida Sinkholes, FL, USA Karst terrain Guilin, China Munching microbes could cleanse arsenic-contaminated groundwater Sulfate-reducing bacteria will consume sulfate and reduce it into sulfide. The sulfide then reacts to precipitate arsenic, leaving little in solution. QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture. QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture. 2005 U. of I. finds solution to arsenic in wells QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture. When the scientists analyzed water from 21 wells, all fed by the Mahomet aquifer in central Illinois, they noticed that the more sulfate they found, the less arsenic there was. Well-water bacteria that are harmless to humans but death on arsenic were responsible, said geology professor Craig Bethke, an author of a paper to be published next month in the journal Geology. "They breathe in sulfate and breathe out sulfide," he said. The sulfide reacts with arsenic, causing it to settle out and never reach the surface. Just add salts That suggests owners of wells with unhealthy levels of arsenic can simply add sulfate, Bethke said. Sulfate salts are inexpensive, readily soluble and easy to find. Qui ckTi me™ and a TIFF (Uncompressed) decompr essor are needed to see this pictur e. Nita Sahai How do our bones and teeth grow? The earliest mineral formed in bone growth is in the nanometer size-range. Previous studies were unable to identify the phase because they relied on traditional methods like X-Ray Diffraction which work best in the micrometer size-range. Identifying the earliest mineral phase that eventually becomes bone (apatite) can help in the development of treatments for osteoporosis and other bone-diseases. Determining the mechanism for heterogeneous apatite precipitation also has environmental applications in remediation of pollutant phosphate.