Speaker
Dr
Farid JUILLOT
(Institut de Mineralogie, de Physique des Materiaux et de Cosmochimie IMPMC, UMR CNRS 7590, UR IRD 206, Universite Pierre et Marie Curie UPMC, 75005 Paris, France)
Description
In this presentation, we will show how Ni K-edge EXAFS data from the Australian Synchrotron (Melbourne) and several facilities worldwide (ESRF-France, ELETTRA-Italy, SOLEIL-France, SSRL-USA) helped us to depict the crystal-chemistry of nickel in New Caledonia, the third nickel producer in the world thanks to its geological setting (one-third of the surface covered with lateritic regoliths resulting from the long-term weathering of peridotites under tropical conditions).
This survey at the molecular environmental level will start in the peridotites (the source of nickel) with data that help to better understand the formation of the hydrous Mg/Ni silicate deposits (i.e. known as garnierite) of New Caledonia.
It will follow in the lateritic regoliths with data that emphasize the vertical change of nickel speciation from Ni-bearing phyllosilicates in the bottom ultramafic bedrock towards Ni-bearing goethite in the upper lateritic horizons (Dublet et al., 2012; 2014; 2015).
Finally, it will end in the mangrove ecosystem with data that show the vertical change of nickel speciation from Ni-bearing goethite towards Ni-bearing pyrite when going from the oxic surface horizons towards the anoxic deep horizons of mangrove sediments located downstream lateritic regoliths (Noel et al., 2014; 2015).
Beyond the single case of New Caledonia, all these informations on the crystal-chemistry of nickel in ultramafic environments shall help building a sustainable exploitation of nickel laterites (60 to 70% of the world’s Ni resources ; Butt and Cluzel, 2013).
| Keywords | Nickel - Speciation - EXAFS - New Caledonia - Peridotites- Garnierites - Laterites - Mangrove - |
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Primary author
Dr
Farid JUILLOT
(Institut de Mineralogie, de Physique des Materiaux et de Cosmochimie IMPMC, UMR CNRS 7590, UR IRD 206, Universite Pierre et Marie Curie UPMC, 75005 Paris, France)
Co-authors
Dr
Cyril Marchand
(Institut de Mineralogie, de Physique des Materiaux et de Cosmochimie IMPMC, UMR CNRS 7590, UR IRD 206, Universite Pierre et Marie Curie UPMC, 75005 Paris, France)
Dr
Emmanuel Fritsch
(Institut de Mineralogie, de Physique des Materiaux et de Cosmochimie IMPMC, UMR CNRS 7590, UR IRD 206, Universite Pierre et Marie Curie UPMC, 75005 Paris, France)
Dr
Gabrielle Dublet
(Institut de Mineralogie, de Physique des Materiaux et de Cosmochimie IMPMC, UMR CNRS 7590, UR IRD 206, Universite Pierre et Marie Curie UPMC, 75005 Paris, France)
Dr
Georges Ona-Nguema
(Institut de Mineralogie, de Physique des Materiaux et de Cosmochimie IMPMC, UMR CNRS 7590, UR IRD 206, Universite Pierre et Marie Curie UPMC, 75005 Paris, France)
Dr
Gordon Brown Jr.
(Department of Geological & Environmental Sciences, Stanford University, Stanford CA 94305-2115, USA)
Mr
Gregory Marakovic
(Koniambo Nickel SAS (KNS), 98860 Kone, New Caledonia)
Dr
Guillaume Morin
(Institut de Mineralogie, de Physique des Materiaux et de Cosmochimie IMPMC, UMR CNRS 7590, UR IRD 206, Universite Pierre et Marie Curie UPMC, 75005 Paris, France)
Dr
Jean-Louis Hazemann
(European Synchrotron Radiation Facility (ESRF), FAME Beamline, F-38043 Grenoble Cedex, France)
Ms
Jessica Brest
(Institut de Mineralogie, de Physique des Materiaux et de Cosmochimie IMPMC, UMR CNRS 7590, UR IRD 206, Universite Pierre et Marie Curie UPMC, 75005 Paris, France)
Dr
Luca Olivi
(Sincrotrone Trieste (ELETTRA), Area Science Park, Strada Statale, 34012 Basovizza, Trieste, Italy)
Ms
Maya Ikogou
(Institut de Mineralogie, de Physique des Materiaux et de Cosmochimie IMPMC, UMR CNRS 7590, UR IRD 206, Universite Pierre et Marie Curie UPMC, 75005 Paris, France)
Dr
Olivier Proux
(European Synchrotron Radiation Facility (ESRF), FAME Beamline, F-38043 Grenoble Cedex, France)
Dr
Stephanie Belin
(Synchrotron SOLEIL, SAMBA Beamline, L'Orme des Merisiers Saint-Aubin - 91192 Gif-sur-Yvette Cedex, France)
Dr
Vincent Noel
(Institut de Mineralogie, de Physique des Materiaux et de Cosmochimie IMPMC, UMR CNRS 7590, UR IRD 206, Universite Pierre et Marie Curie UPMC, 75005 Paris, France)
