|[EntetePerso nom=”Garçon” prenom=”Marion” commentaire=””]|
I use chemical and isotopic compositions (mainly Sm-Nd, Lu-Hf, Rb-Sr, and U-Th-Pb isotopic systems) of modern sediments or ancient sedimentary rocks to study the origin, composition, and evolution of the continents and the oceans through time.
Detrital sediments and sedimentary rocks such as sandstone or shale are mixtures of mineral grains derived from the erosion of continents. I am interested in the chemical and isotopic signatures of these minerals because they record precious information on geological and sedimentary processes acting on continents as well as on the composition and the formation of crustal rocks.
Chemical sedimentary rocks such as banded iron formation, carbonate, or chert that formed in seawater can trap complementary information on the composition of seawater, the oxygenation of the atmosphere and oceans, and the interactions between oceans and continents. In my research, I use chemical sedimentary rocks to better understand past environmental conditions at the beginning of Earth history.
At the scale of the global sedimentary system, I am also interested in the recycling of sedimentary materials in subduction zones and the effects that such a process may have on the long-term evolution of the mantle and crust compositions.
I am currently involved in several projects looking at ancient detrital and chemical sediments from different Archean cratons worldwide. Most of my current researches are however focused on banded iron formations as part of my ERC Starting grant project.
ERC Stating grant GOforISOBIF (2020-2025)
Since the beginning of Earth’s history, the oceans acted as an interface between the atmosphere, the continents, and the mantle via atmospheric exchange, weathering, sedimentation, and submarine volcanism. Such interactions make the composition of early seawater a unique recorder of the processes that have affected the Earth’s major reservoirs. Yet, this record has not been explored in details.
Here, I propose to investigate the geochemistry of the first oceans that is recorded in Precambrian banded iron formations (BIFs) to address first-order questions related to the early evolution of our planet. The proposed project combines well-established radiogenic isotopic systems with novel and highly promising stable isotope tracers that will be developed as part of the project. These geochemical proxies will be measured on a unique collection of BIF samples deposited from ~3.8 to 0.7 Ga ago with the following objectives:
(1) determine the origin, composition, and size of the first continents,
(2) detect whiffs of oxygen in the early oceans in various depositional settings before and after the Great Oxidation Event (GOE),
(3) identify the periods of intense hydrothermal activity through Earth’s history and link them to global mantle geodynamics.
The proposed project will promote the application of state-of-the-art isotopic measurements, with an emphasis on further methodological development to set-up new isotope proxies. This innovative approach is needed to test previously suggested hypotheses, develop new ideas, and to tackle the challenging questions of the early Earth evolution from a different angle.
Quentin Aquila (2021 – 2024)
Lukas Nicol (2021 – 2024)
Pierre Bonnand (Postdoc, 2021 – present)
Quentin Aquila (2020)
Nicolas Olivier (LMV Clermont-Ferrand)
Maud Boyet (LMV Clermont-Ferrand)
Andrey Bekker (University of California, Riverside)
2019 – Chargé de Recherche CNRS, Laboratoire Magmas et Volcans, Clermont-Ferrand, France
2016 – 2019 Ambizione Fellowship, ETH Zürich, Switzerland
2015 – 2016 Auvergne Fellowship, Laboratoire Magmas et Volcans, Clermont-Ferrand, France
2013 – 2015 Postdoctoral Fellowship, Carnegie Institution of Washington, USA
2013 Lab Engineer in Geochemistry, University of Grenoble, France
2009 – 2012 PhD in Earth Sciences – Geochemistry, University of Grenoble, France – Advisor: Catherine Chauvel
2007 – 2009 M.Sc. in Earth Sciences, University of Grenoble, France
2004 – 2007 B.Sc. in Physics, major Physics and Chemistry, University of Grenoble, France
Rang A :[Publications nom=”Garçon” prenom=”Marion” rang=”Rang A”]
Rang B et C :[Publications nom=”Garçon” prenom=”Marion” rang=”Rang B-C”]
Boyet M., Bouvier A., Frossard P., Hammouda T., Garçon M., Gannoun A., Enstatite chondrites EL3 as building blocks for the Earth: the debate over the 146Sm-142Nd systematics. Earth and Planetary Science Letters, 488, 68-78. DOI: 10.1016/j.epsl.2018.02.004
Henshall T., Cook D.L., Garçon M., Schönbächler M., High-precision Strontium isotope analysis of geological samples by thermal ionisation mass spectrometry. Chemical Geology, 482, 113-120. DOI: 10.1016/j.chemgeo.2018.02.010
Horan M.F., Carlson R.W., Walker R.J., Jackson M., Garçon M., Norman M., Tracking Hadean processes in modern basalts with 142-Neodymium. Earth and Planetary Science Letters, 484, 184-191 (2018). DOI: 10.1016/j.epsl.2017.12.017
Garçon M., Carlson R.W., Shirey S.B., Arndt N.T., Horan M.F., Mock T.D., Erosion of Archean continents: The Sm-Nd and Lu-Hf isotopic record of Barberton sedimentary rocks. Geochimica et Cosmochimica Acta, 206, 216-235 (2017). DOI: 10.1016/j.gca.2017.03.006
Garçon M., Sauzéat L., Carlson R.W., Shirey S.B., Simon M., Balter V., Boyet M., Nitrile, Latex, Neoprene and Vinyl Gloves: A Primary Source of Contamination for Trace Element and Zn Isotopic Analyses in Geological and Biological Samples. Geostandards and Geoanalytical Research, 41, 3, 367-380 (2017). DOI: 10.1111/ggr.12161
Sauzéat L., Rudnick R.L., Chauvel C., Garçon M., Tang M., New perspectives on the Li isotopic composition of the upper continental crust and its weathering signature (2015). Earth and Planetary Science Letters, 428, 181-192.
Guillot S., Garçon M., Weinman B., Gajurel A., Tisserand D., France-Lanord C., Geen A., Chakraborty S., Huyghe P., Upreti B.N., Charlet L., Origin of Arsenic anomalies in Late Pleistocene to Holocene sediments in the Nawalparasi District (Terai, Nepal) (2015). Environmental Earth Sciences, doi: 10.1007/s12665-015-4277-y
Garçon M., Chauvel C., Where is basalt in river sediments and why does it matters? (2014). Earth and Planetary Science Letters, 407, 61-69.
Garçon M., Chauvel C., France-Lanord C., Limonta M., Garzanti E., Which minerals control Nd-Hf-Sr-Pb isotopic compositions of river sediments? (2014). Chemical Geology, 364, 42-55.
Chauvel C., Garçon M., Bureau S., Besnault A., Jahn B.-M., Ding Z., Constraints from loess on the Hf-Nd isotopic composition of the upper continental crust (2014). Earth and Planetary Science Letters, 388, 48-58.
Simonneau A., Chapron E., Garçon M., Winiarski T., Graz Y., Chauvel C., Debret M., Motellica-Heino M., Desmet M., Di Giovanni C., Tracking Holocene glacial and high-altitude alpine environments fluctuations from minerogenic and organic markers in proglacial lake sediments (Lake Blanc Huez, Western French Alps) (2014).Quaternary Science Reviews, 89, 27-43.
Garçon M., Chauvel C., France-Lanord C., Limonta M., Garzanti E., Removing the “heavy mineral effect” to obtain a new Pb isotopic value for the upper crust (2013). Geochemistry Geophysics Geosystems, 14, 9, doi: 10.1002/ggge.20219
Garçon M., Chauvel C., France-Lanord C., Huyghe P., Lave J., Sedimentary processes decouple Nd-Hf isotopes in river sediments on continents (2013). Geochimica et Cosmochimica Acta 121, 177-195.
Garçon M., Chauvel C., Chapron E., Fain X., Lin M., Campillo S., Bureau S., Desmet M., Bailly-Maitre M.-C., Charlet L., Silver and lead in high-altitude lake sediments: Proxies for climate changes and human activities(2012). Applied Geochemistry, 27,3, 760-773
Garçon M., Chauvel C., Bureau S. Beach placer, a proxy for the average Nd and Hf isotopic composition of a continental area (2011). Chemical Geology, 287, 3-4, 182-192
Expedition 333 Scientists, including Garçon M.. NanTroSEIZE Stage 2: subduction inputs 2 and heat flow. IODP Prel. Rept., 333(2011). doi:10.2204/iodp.pr.333.2011