Search Results - "Johnson, Aleisha C."

Clues from Ab Initio Calculations on Titanium Isotopic Fractionation in Tholeiitic and Calc-Alkaline Magma Series by Aarons, Sarah M, Dauphas, Nicolas, Blanchard, Marc, Zeng, Hao, Nie, Nicole Xike, Johnson, Aleisha C, Greber, Nicolas D, Hopp, Timo

“…Magmatic differentiation produces positive correlations between δ49Ti and SiO2. The equilibrium Ti isotope fractionation factors of Ti-bearing minerals are…”
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Earth's First Redox Revolution by Ostrander, Chadlin M, Johnson, Aleisha C, Anbar, Ariel D

“…The rise of molecular oxygen (O 2 ) in the atmosphere and oceans was one of the most consequential changes in Earth's history. While most research focuses on…”
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Titanium isotopic fractionation in Kilauea Iki lava lake driven by oxide crystallization by Johnson, Aleisha C., Aarons, Sarah M., Dauphas, Nicolas, Nie, Nicole Xike, Zeng, Hao, Helz, Rosalind T., Romaniello, Stephen J., Anbar, Ariel D.

“…Recent work has demonstrated that titanium (Ti) isotopes undergo mass-dependent isotope fractionation during magmatic differentiation, leaving evolved silicic…”
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Assessing molybdenum isotope fractionation during continental weathering as recorded by weathering profiles in saprolites and bauxites by Greaney, Allison T., Rudnick, Roberta L., Romaniello, Stephen J., Johnson, Aleisha C., Anbar, Ariel D., Cummings, Michael L.

“…Molybdenum isotopes in three deep and well-characterized weathering profiles – a saprolite formed on meta-diabase from South Carolina, USA, and two ferruginous…”
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Reconciling evidence of oxidative weathering and atmospheric anoxia on Archean Earth by Johnson, Aleisha C, Ostrander, Chadlin M, Romaniello, Stephen J, Reinhard, Christopher T, Greaney, Allison T, Lyons, Timothy W, Anbar, Ariel D

“…Evidence continues to emerge for the production and low-level accumulation of molecular oxygen (O ) at Earth’s surface before the Great Oxidation Event…”
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Technical comment on "Reexamination of 2.5-Ga 'whiff' of oxygen interval points to anoxic ocean before GOE" by Anbar, Ariel D, Buick, Roger, Gordon, Gwyneth W, Johnson, Aleisha C, Kendall, Brian, Lyons, Timothy W, Ostrander, Chadlin M, Planavsky, Noah J, Reinhard, Christopher T, Stüeken, Eva E

“…Many lines of inorganic geochemical evidence suggest transient "whiffs" of environmental oxygenation before the Great Oxidation Event (GOE). Slotznick assert…”
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Redox and mineral controls on Fe and Ti isotopic fractionations during calc-alkaline magmatic differentiation by Johnson, Aleisha C., Zhang, Zhe J., Dauphas, Nicolas, Rudnick, Roberta L., Foden, John D., Toc, Magali

“…Titanium and Fe isotopic compositions of lavas from a calc-alkaline differentiation suite and corresponding mineral separates from the Rindjani Volcano,…”
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Molybdenum isotope fractionation in glacial diamictites tracks the onset of oxidative weathering of the continental crust by Greaney, Allison T., Rudnick, Roberta L., Romaniello, Stephen J., Johnson, Aleisha C., Gaschnig, Richard M., Anbar, Ariel D.

“…•Glacial diamictites record changes in chemical weathering of the crust.•Diamictites formed before the GOE have similar δ98Mo values as igneous…”
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Titanium and iron isotopic records of granitoid crust production in diverse Archean cratons by Zhang, Zhe J., Dauphas, Nicolas, Johnson, Aleisha C., Aarons, Sarah M., Bennett, Vickie C., Nutman, Allen P., MacLennan, Scott, Schoene, Blair

“…Archean granitoid provides critical clues on how Earth's felsic crust was established and its geodynamics evolved. In this study, we present Fe-Ti isotope and…”
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Experimental determination of pyrite and molybdenite oxidation kinetics at nanomolar oxygen concentrations by Johnson, Aleisha C., Romaniello, Stephen J., Reinhard, Christopher T., Gregory, Daniel D., Garcia-Robledo, Emilio, Revsbech, Niels Peter, Canfield, Donald E., Lyons, Timothy W., Anbar, Ariel D.

“…Constraining the rate at which sulfide minerals undergo oxidative weathering at low atmospheric O2 is crucial for understanding the evolution of the Archean…”
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Investigations into Crustal Composition and Oxidative Weathering in the Archean by Johnson, Aleisha C

“…Archean oxidative weathering reactions were likely important O2 sinks that delayed the oxygenation of Earth’s atmosphere, as well as sources of bio-essential…”
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The Importance of Prioritizing Exoplanet Experimental Facilities by Kohler, Erika, He, Chao, Moran, Sarah E, Shim, S. -H. Dan, Brugman, Karalee K, Johnson, Aleisha C, Vergeli, Pilar C, Thompson, Maggie A, Graham, Heather, Gudipati, Murthy S, Fleury, Benjamin, Henderson, Bryana L

“…Continuous improvements of observations and modeling efforts have led to tremendous strides in exoplanetary science. However, as instruments and techniques…”
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