A Combined Carbon and Oxygen Isotopic Analysis of Alh84001 Carbonates with Nanosims
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منابع مشابه
Carbon and Oxygen Isotopic Systematics in Calcite and Dolomite from the Sangan Iron Skarn Deposit, Northeastern Iran
A total of 40 samples from carbonates and 8 samples from silicate rocks were analyzed from the Sangan iron skarn deposit to examine behavior of the oxygen and carbon isotopes. The higher values of ?18O are from metamorphic calcite and dolomite and lower ones are from granitic rocks. Although the ?18O and ?13C values of calcite and dolomite in marble yield the highest values in the Sangan deposi...
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The debate of life on Mars centers around the source of the globular, micrometer-sized mineral carbonates in the ALH84001 meteorite; consequently, the identification of Martian processes that form carbonates is critical. This paper reports a previously undescribed carbonate formation process that occurs on Earth and, likely, on Mars. We identified micrometer-sized carbonates in terrestrial aero...
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Despite evidence for liquid water at the surface of Mars during the Noachian epoch, the temperature of early aqueous environments has been impossible to establish, raising questions of whether the surface of Mars was ever warmer than today. We address this problem by determining the precipitation temperature of secondary carbonate minerals preserved in the oldest known sample of Mars’ crust—the...
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