Damien Guinoiseau (Post-doc)

Identification of weathering processes in Amazonian lateritic profiles combining Si and Li isotope signatures

In this post-doc project, we decided to constrain the main weathering processes occurring throughout Amazonian lateritic profiles by applying stable isotope geochemistry. We focus our work on the use of Li and Si isotopes that, both, are excellent tracers of chemical weathering due to the isotope fractionation occurring during the formation of secondary minerals (especially clays). Four lateritic profiles, spanned over the Guyana Shield, were selected to obtain a range of substrate, soil thickness and ages. Analysis are performed on the bulk soils as well as on the purified clay fractions to strengthen the “geochemical information” recorded by Si and Li isotopes. By combining this isotope approach with conventional geochemistry (cf. Claire Ansart profile) and datation techniques (e.g. Beatrix Heller profile), we will be able to determine the timing and the intensity of weathering episodes occurring in the Guyana Shield region from 60 Ma to now.

Publications

Guinoiseau D., Galer S.J.G., Abouchami W., Frank M., Achterberg E.P. & Haug G.H. (Accepted) Importance of cadmium sulfides for biogeochemical cycling of Cd and its isotopes in Oxygen Deficient Zones – a case study of the Angola Basin. Global Biogeochemical Cycles

Weber M., Lugli F., Hattendorf B., Scholz D., Mertz‐Kraus R., Guinoiseau D. & Jochum K.P. (2019) NanoSr – A New Carbonate Microanalytical Reference Material for In Situ Strontium Isotope Analysis. Geostandards and Geoanalytical Research

Guinoiseau D., Galer S.J.G. & Abouchami W. (2018) Effect of cadmium sulphide precipitation on the partitioning of Cd isotopes: implications for the oceanic Cd cycle. Earth and Planetary Science Letters, 498, 300-308.

Guinoiseau D., Bouchez J., Gélabert A., Louvat P. Moreira-Turcq P., Filizola N. & Benedetti M.F. (2018) Fate of particulate copper and zinc isotopes at the Solimões-Negro river confluence, Amazon Basin, Brazil. Chemical Geology, 489, 1-15.

Guinoiseau D., Louvat P., Paris G., Chen J-B., Chetelat B., Rocher V., Guerin S. & Gaillardet J. (2018) Are boron isotopes a reliable tracer of anthropogenic inputs to rivers over time? Science of the Total Environment, 626, 1057-1068.

Guinoiseau D., Gélabert A., Allard T., Louvat P., Moreira-Turcq P. & Benedetti M.F. (2017) Zinc and copper behaviour at the soil-river interface: new insights by Zn and Cu isotopes in the organic-rich Rio Negro basin. Geochimica et Cosmoschimica Acta, 213, 178-197.

Guinoiseau D., Gélabert A., Louvat P., Moureau J. & Benedetti M.F. (2016) Zinc isotope fractionation during sorption onto kaolinite. Environmental Science & Technology, 50, 1844-1852.

Guinoiseau D., Bouchez J., Gélabert A., Louvat P., Filizola N., & Benedetti M.F. (2016) The geochemical filter of large river confluences. Chemical Geology, 441, 291-303.

Short CV

Since 07/2019: Post-doc position – Université de Paris-IPGP/CEREGE.

Identification of weathering processes in Amazonian lateritic profiles combining Si and Li isotope signatures

03/2017-06/2019: Post-doc fellow – Max Planck Institute for Chemistry, Mainz, GERMANY.

Project 1: Understanding the biogeochemical cycle of cadmium and its isotopes in the ocean

Project 2: Determination of African dust contribution to fertilization in the Amazon Basin

11/2016-12/2016: Engineer in chemical analysis – IPGP/Paris Diderot University .

Impact of small Peruvian catchments on the weathering budget of the Amazon Basin. Field trip in 2016 to collect river waters and sediments.

09/2012-06/2016: PhD and teaching assistant – IPGP/Paris Diderot University .

Impact of physico-chemical processes at water-rock interfaces on the behavior of Zn and Cu isotopes in laboratory and natural systems: application to the Amazonian Basin.

09/2011-07/2012: Master Degree in geochemistry – IPGP/Paris Diderot University

Boron isotopes as tracers of anthropogenic sources in the Seine River basin.

Conference presentations

African dust sources contributing to fertilization in the Amazon basin. Goldschmidt Conference 2019 (Barcelona – USA) (Flash talk + poster)

Dust source identification in the Amazon Basin combining chemical and isotopic approaches. AGU Conference 2018 (Washington – USA) (Poster)

Importance of cadmium sulphides for Cd cycling in the Oxygen Deficient Zone of the Angola Basin. Goldschmidt Conference 2018 (Boston – USA) (Talk)

Effect of cadmium sulphide precipitation on the partitioning of Cd isotopes: implications for Cd oceanic cycle. EGU Conference 2018 (Vienna – Austria) (Poster)

Effect of CdS precipitation on the partitioning of Cd isotopes. Goldschmidt Conference 2017 (Paris – France) (Poster)

Zinc dynamic across the Rio Negro basin: constraints from Zn isotopes. Goldschmidt Conference 2016 (Yokohama – Japan) (Talk)

Zinc isotope fractionation onto reactive minerals: the case of kaolinite. Goldschmidt Conference 2015 (Prague – Czech Republic) (Talk)

Zinc and copper isotope fate in the Amazonian mixing zone. Réunion des Sciences de la Terre (Pau – France) (Talk)

Zinc and copper isotope fate in the Amazonian mixing zone. Goldschmidt Conference 2014 (Sacramento – USA) (Poster)