Search Results - "MacLennan, Scott"

Polyphase Zircon Growth during Slow Cooling from Ultrahigh Temperature: an Example from the Archean Pikwitonei Granulite Domain by Guevara, Victor E, MacLennan, Scott A, Dragovic, Besim, Caddick, Mark J, Schoene, Blair, Kylander-Clark, Andrew R C, Couëslan, Chris G

“…Abstract Quantifying the timescales of Archean ultrahigh temperature (UHT) metamorphism is essential for constraining the style of plate tectonics on the early…”
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Geologic evidence for an icehouse Earth before the Sturtian global glaciation by MacLennan, Scott A., Eddy, Michael P., Merschat, Arthur J., Mehra, Akshay K., Crockford, Peter W., Maloof, Adam C., Southworth, C. Scott, Schoene, Blair

“…Tropical glaciers imply that Earth was already cold before the first Neoproterozoic Snowball Earth. Snowball Earth episodes, times when the planet was covered…”
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From a proximal-deposition-dominated basin sink to a significant sediment source to the Chinese Loess Plateau: Insight from the quantitative provenance analysis on the Cenozoic sediments in the Qaidam basin, northern Tibetan Plateau by Wang, Lin, MacLennan, Scott A., Cheng, Feng

“…•Kunlun Shan is the primary sediment source of Paleogene strata for SW Qaidam Basin.•Topography separated the Qaidam Basin from the Hoh Xil Basin in the…”
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Reliability of detrital marine sediments as proxy for continental crust composition: The effects of hydrodynamic sorting on Ti and Zr isotope systematics by Klaver, Martijn, MacLennan, Scott A., Ibañez-Mejia, Mauricio, Tissot, François L.H., Vroon, Pieter Z., Millet, Marc-Alban

“…The isotopic composition of the detrital sediment record harbours a valuable proxy for estimating the composition of the erodible upper crust since the…”
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Paleogeography and high-precision geochronology of the Neoarchean Fortescue Group, Pilbara, Western Australia by Kasbohm, Jennifer, Schoene, Blair, Maclennan, Scott A., Evans, David A.D., Weiss, Benjamin P.

“…[Display omitted] •We present 6 paleomagnetic poles and 4 U-Pb ID-TIMS ages for the Fortescue Group.•At ∼2.77 Ma we estimate minimum rates from 23 ± 20 cm/a to…”
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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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Extremely rapid, yet noncatastrophic, preservation of the flattened-feathered and 3D dinosaurs of the Early Cretaceous of China by MacLennan, Scott A., Sha, Jingeng, Olsen, Paul E., Kinney, Sean T., Chang, Clara, Fang, Yanan, Liu, Jun, Slibeck, Bennett B., Chen, Elaine, Schoene, Blair

“…Northeast China’s Early Cretaceous Yixian Formation preserves spectacular fossils that have proved extraordinarily important in testing evolutionary hypotheses…”
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Temperature and co-crystallization effects on Zr isotopes by Kirkpatrick, Heather M., Harrison, T. Mark, Ibañez-Mejia, Mauricio, Tissot, François L.H., MacLennan, Scott A., Bell, Elizabeth A.

“…We undertook Zr isotope measurements on zircon, titanite, biotite, amphibole, and whole rocks from the La Posta pluton (Peninsular Ranges, southern California)…”
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Geochemical Reservoirs and Timing of Sulfur Cycling on Mars by Gaillard, Fabrice, Michalski, Joseph, Berger, Gilles, McLennan, Scott M., Scaillet, Bruno

“…Sulfate-dominated sedimentary deposits are widespread on the surface of Mars, which contrasts with the rarity of carbonate deposits, and indicates surface…”
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GHR1 Zircon – A New Eocene Natural Reference Material for Microbeam U‐Pb Geochronology and Hf Isotopic Analysis of Zircon by Eddy, Michael P., Ibañez‐Mejia, Mauricio, Burgess, Seth D., Coble, Matthew A., Cordani, Umberto G., DesOrmeau, Joel, Gehrels, George E., Li, Xianhua, MacLennan, Scott, Pecha, Mark, Sato, Kei, Schoene, Blair, Valencia, Victor A., Vervoort, Jeffrey D., Wang, Tiantian

“…We present multitechnique U‐Pb geochronology and Hf isotopic data from zircon separated from rapakivi biotite granite within the Eocene Golden Horn batholith…”
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Temporal Constraints on Archean Crustal Geodynamics and Neoproterozoic Glaciation by MacLennan, Scott Angus

“…Secular cooling of Earth's mantle today is achieved via convection, and conductive heat loss through the lithosphere. The formation of the oceanic lithosphere…”
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GHR 1 Zircon – A New Eocene Natural Reference Material for Microbeam U‐Pb Geochronology and Hf Isotopic Analysis of Zircon by Eddy, Michael P., Ibañez‐Mejia, Mauricio, Burgess, Seth D., Coble, Matthew A., Cordani, Umberto G., DesOrmeau, Joel, Gehrels, George E., Li, Xianhua, MacLennan, Scott, Pecha, Mark, Sato, Kei, Schoene, Blair, Valencia, Victor A., Vervoort, Jeffrey D., Wang, Tiantian

“…We present multitechnique U‐Pb geochronology and Hf isotopic data from zircon separated from rapakivi biotite granite within the Eocene Golden Horn batholith…”
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THE CONDENSATION OF CERTAIN METHYLKETONES WITH ISATIN BY THE KNOEVENAGEL METHOD by MACLENNAN, JOHN SCOTT

“…The purpose of this investigation has been to study the condensation reactions of Isatin with certain methyl ketones by means of mild condensing agents of the…”
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