Search Results - "Lalonde, Stefan"

Benthic perspective on Earth’s oldest evidence for oxygenic photosynthesis by Lalonde, Stefan V., Konhauser, Kurt O.

“…The Great Oxidation Event (GOE) is currently viewed as a protracted process during which atmospheric oxygen increased above ∼10 ⁻⁵ times the present…”
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Geochemistry of carbonate microbialites through time and space: Insights from the microbialite collection of the Muséum National d'Histoire Naturelle (MNHN), France by Fogret, Laurane, Sansjofre, Pierre, Lalonde, Stefan V.

“…Microbialites are microbial sedimentary structures that constitute some of the oldest traces of life on Earth. By their deposition in a wide range of…”
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Proterozoic ocean redox and biogeochemical stasis by Reinhard, Christopher T., Planavsky, Noah J., Robbins, Leslie J., Partin, Camille A., Gill, Benjamin C., Lalonde, Stefan V., Bekker, Andrey, Konhauser, Kurt O., Lyons, Timothy W.

“…The partial pressure of oxygen in Earth’s atmosphere has increased dramatically through time, and this increase is thought to have occurred in two rapid steps…”
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Evidence for oxygenic photosynthesis half a billion years before the Great Oxidation Event by Planavsky, Noah J., Asael, Dan, Hofmann, Axel, Reinhard, Christopher T., Lalonde, Stefan V., Knudsen, Andrew, Wang, Xiangli, Ossa Ossa, Frantz, Pecoits, Ernesto, Smith, Albertus J. B., Beukes, Nicolas J., Bekker, Andrey, Johnson, Thomas M., Konhauser, Kurt O., Lyons, Timothy W., Rouxel, Olivier J.

“…The evolution of oxygenic photosynthesis should have occurred some time before the oxidation of Earth’s atmosphere 2.5 billion years ago. The molybdenum…”
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Microbial life and biogeochemical cycling on land 3,220 million years ago by Homann, Martin, Sansjofre, Pierre, Van Zuilen, Mark, Heubeck, Christoph, Gong, Jian, Killingsworth, Bryan, Foster, Ian S., Airo, Alessandro, Van Kranendonk, Martin J., Ader, Magali, Lalonde, Stefan V.

“…The colonization of emergent continental landmass by microbial life was an evolutionary step of paramount importance in Earth history. Here we report direct…”
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Globally asynchronous sulphur isotope signals require re-definition of the Great Oxidation Event by Philippot, Pascal, Ávila, Janaína N., Killingsworth, Bryan A., Tessalina, Svetlana, Baton, Franck, Caquineau, Tom, Muller, Elodie, Pecoits, Ernesto, Cartigny, Pierre, Lalonde, Stefan V., Ireland, Trevor R., Thomazo, Christophe, van Kranendonk, Martin J., Busigny, Vincent

“…The Great Oxidation Event (GOE) has been defined as the time interval when sufficient atmospheric oxygen accumulated to prevent the generation and preservation…”
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Aerobic bacterial pyrite oxidation and acid rock drainage during the Great Oxidation Event by Konhauser, Kurt O., Lalonde, Stefan V., Planavsky, Noah J., Pecoits, Ernesto, Lyons, Timothy W., Mojzsis, Stephen J., Rouxel, Olivier J., Barley, Mark E., Rosìere, Carlos, Fralick, Phillip W., Kump, Lee R., Bekker, Andrey

“…Metal-respiring bacteria as atmospheric oxidation agents Free oxygen appeared in Earth's atmosphere for the first time around 2.5 billion years ago, in what is…”
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Localized geochemical variability produced by depositional and diagenetic processes in a 2.8 Ga Ca-carbonate system: A cautionary paradigm by Fralick, Philip, Himmler, Tobias, Lalonde, Stefan V., Riding, Robert

“…•This work explores the roles of depositional and diagenetic processes that operated on an Archean carbonate platform.•Micro-analytical techniques (scanning…”
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Palaeoproterozoic oxygenated oceans following the Lomagundi–Jatuli Event by Mänd, Kaarel, Lalonde, Stefan V., Robbins, Leslie J., Thoby, Marie, Paiste, Kärt, Kreitsmann, Timmu, Paiste, Päärn, Reinhard, Christopher T., Romashkin, Alexandr E., Planavsky, Noah J., Kirsimäe, Kalle, Lepland, Aivo, Konhauser, Kurt O.

“…The approximately 2,220–2,060 million years old Lomagundi–Jatuli Event was the longest positive carbon isotope excursion in Earth history and is traditionally…”
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Oceanic nickel depletion and a methanogen famine before the Great Oxidation Event by Konhauser, Kurt O., Pecoits, Ernesto, Lalonde, Stefan V., Papineau, Dominic, Nisbet, Euan G., Barley, Mark E., Arndt, Nicholas T., Zahnle, Kevin, Kamber, Balz S.

“…Whys after the Event The Great Oxidation Event (GOE), an era on Earth about 2.4 billion years ago when oxygen began to accumulate in the atmosphere, is widely…”
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Iron from continental weathering dictated soft‐part preservation during the Early Ordovician by Saleh, Farid, Lucas, Victoire, Pittet, Bernard, Lefebvre, Bertrand, Lalonde, Stefan V., Sansjofre, Pierre

“…The Fezouata Shale in Morocco is the most diverse Lower Ordovician unit yielding soft‐tissue preservation. Iron played a crucial role in the preservation of…”
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Cu isotopes in marine black shales record the Great Oxidation Event by Fru, Ernest Chi, Rodríguez, Nathalie P., Partin, Camille A., Lalonde, Stefan V., Andersson, Per, Weiss, Dominik J., Albani, Abderrazak El, Rodushkin, Ilia, Konhauser, Kurt O.

“…The oxygenation of the atmosphere ∼2.45–2.32 billion years ago (Ga) is one of the most significant geological events to have affected Earth’s redox history…”
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The evolution of the marine phosphate reservoir by Lyons, Timothy W, Planavsky, Noah J, Rouxel, Olivier J, Bekker, Andrey, Lalonde, Stefan V, Konhauser, Kurt O, Reinhard, Christopher T

“…Phosphorus is a biolimiting nutrient that has an important role in regulating the burial of organic matter and the redox state of the ocean-atmosphere system…”
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Hydrogeological constraints on the formation of Palaeoproterozoic banded iron formations by Robbins, Leslie J., Funk, Sean P., Flynn, Shannon L., Warchola, Tyler J., Li, Zhiquan, Lalonde, Stefan V., Rostron, Benjamin J., Smith, Albertus J. B., Beukes, Nicolas J., de Kock, Michiel O., Heaman, Larry M., Alessi, Daniel S., Konhauser, Kurt O.

“…Banded iron formations are critical to track changes in Archaean to Palaeoproterozoic ocean chemistry, with deposition triggered by water column iron…”
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Cobalt and marine redox evolution by Swanner, Elizabeth D., Planavsky, Noah J., Lalonde, Stefan V., Robbins, Leslie J., Bekker, Andrey, Rouxel, Olivier J., Saito, Mak A., Kappler, Andreas, Mojzsis, Stephen J., Konhauser, Kurt O.

“…Cobalt (Co) is a bio-essential trace element and limiting nutrient in some regions of the modern oceans. It has been proposed that Co was more abundant in…”
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Variable Ni isotope fractionation between Fe-oxyhydroxides and implications for the use of Ni isotopes as geochemical tracers by Gueguen, Bleuenn, Sorensen, Jeffry V., Lalonde, Stefan V., Peña, Jasquelin, Toner, Brandy M., Rouxel, Olivier

“…Nickel (Ni) isotopes have recently emerged as a new biogeochemical tracer in marine environments, but our understanding of the mechanisms of Ni isotope…”
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The Joffre banded iron formation, Hamersley Group, Western Australia: Assessing the palaeoenvironment through detailed petrology and chemostratigraphy by Haugaard, Rasmus, Pecoits, Ernesto, Lalonde, Stefan, Rouxel, Olivier, Konhauser, Kurt

“…•We present petrology and geochemistry of the largest single known banded iron formation in the world.•Dominant rock types are oxide BIF,…”
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Possible evolution of mobile animals in association with microbial mats by Gingras, Murray, Hagadorn, James W., Seilacher, Adolf, Lalonde, Stefan V., Pecoits, Ernesto, Petrash, Daniel, Konhauser, Kurt O.

“…The evolution of marine complex animals about 635 million years ago took place in relatively low-oxygen waters. An analysis of a low-oxygen, hypersaline lagoon…”
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The Archean Nickel Famine Revisited by Konhauser, Kurt O, Robbins, Leslie J, Pecoits, Ernesto, Peacock, Caroline, Kappler, Andreas, Lalonde, Stefan V

“…Iron formations (IF) preserve a history of Precambrian oceanic elemental abundance that can be exploited to examine nutrient limitations on early biological…”
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A Mesoarchean shift in uranium isotope systematics by Wang, Xiangli, Planavsky, Noah J., Hofmann, Axel, Saupe, Erin E., De Corte, Brian P., Philippot, Pascal, LaLonde, Stefan V., Jemison, Noah E., Zou, Huijuan, Ossa, Frantz Ossa, Rybacki, Kyle, Alfimova, Nadezhda, Larson, Matthew J., Tsikos, Harilaos, Fralick, Philip W., Johnson, Thomas M., Knudsen, Andrew C., Reinhard, Christopher T., Konhauser, Kurt O.

“…Oxygenic photosynthesis fundamentally transformed all major biogeochemical cycles and increased the size and complexity of Earth's biosphere. However, there is…”
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