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Isotopic systematics of ultramafic and mafic rocks of the Taitao ophiolite, southern Chile
A variety of ultramafic and mafic rocks from a well-mapped sampling of the ~6 Ma Taitao Ophiolite, Chile, have been examined. Calculated initial 187Os/188Os ratios of the peridotitic rocks range from 0.1168 to 0.1282. ...
Sulfur isotope fractionations in biological systems: insight into the Proterozoic biosphere
This study focuses on developing a framework for interpreting isotopic fractionations in the four stable sulfur isotopes, with a special focus on microbial effects. Calculations of low temperature equilibrium fractionations ...
Isotope and Organic Geochemistry of a Unique Proterozoic, Postglacial Succession: The Lapa Formation, Vazante Group, Brazil
This study is the second to investigate biological characteristics associated with Proterozoic glaciation via molecular fossils from organic matter preserved in shale. In the Vazante Group, Minas Gerais, Brazil, the Serra ...
Experimental study of the partitioning of Cu, Ag, Au, Mo and W among pyrrhotite and immiscible Fe-S-O and silicate melts
Partition coefficients have been determined for several transition metals amongst a rhyolitic silicate melt, pyrrhotite, and an immiscible Fe-S-O melt. Two sets of experiments were performed in sealed silica tubes at ...
A Geochemical and Osmium Isotopic Study of Group IVB Irons and Ungrouped Irons Chinga, Tishomingo and Willow Grove
Re-Os isotopic and highly siderophile element (HSE) systematics of IVB irons and ungrouped iron meteorites Chinga, Tishomingo and Willow Grove are presented. IVB iron composition has been constrained by HSE (Re, Os, Ru, ...