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The second year of this project saw the completion of a major milestone with the preparation of an article detailing our work on revision of the lead carbonate (cerussite) oxygen stable isotope thermometer. This article is presently in review at Geochimica et Cosmochimica Acta. In this work, the reason for discrepancy between experimental and empirical geothermometers was examined. It was determined, using detailed SEM/EDS studies, that previous work on this thermometer utilized rapid precipitation experiments that yielded hydrocerussite cores on some grains. This in turn produced incorrect fractionation determinations for the cerussite-water system. The article in review presents this new work, reviews other recent work on lead carbonate isotope systematics, and establishes new oxygen stable isotope thermometers for both the cerussite-water and hydroserussite-water systems.

Our nitrogen isotope work on samples collected from the Atacama Desert of Chile has proceeded during the year. Nitrogen and oxygen stable isotope analyses of these materials were hindered by the presence of high levels of other salts in the samples. As a result, a more complex extraction was required, with samples undergoing leaching, followed by nitrate stripping using selective ion resin columns. The collected nitrate was then eluted for final sample preparation and isotopic analysis. In addition, potential copper nitrate (Gerhardtite) samples were examined from several mines visited during the 2009 field season. In three of the samples, the phase was confirmed by our work as Gerhardtite, identifying these sites as new  occurrences for this rare mineral. All samples collected during the 2009 field season have now been analyzed and preliminary examination of the data suggest that the copper nitrate minerals form exclusively during an isotopically distinct late event.

A key component of our work has been undergraduate student experiential learning. The second year of this work saw all year 1 student participants graduate, and a significant number of potential participants drop out of school or take outside employment with higher pay or benefits. The economic crisis has hit the students of our program and university particularly hard, as our service area is dominated by economically disadvantaged non-traditional students from groups historically underrepresented in the sciences. The result has been extreme difficulty in recruiting qualified and motivated students, as compared to year 1. This difficulty was overcome through a variety of motivational techniques that were presented as an oral geoscience educational program at the 2010 NASA Astrobiology Conference, entitled “Stable Isotope Geochemistry at Hispanic Serving Institutions: Si, se puede!”