RT6 – Stable Isotopes’ Geochemistry

Explore and understand, through observation, experimentation, and theoretical approaches, variations in isotopic fractionation at the elemental scale (e.g., Fe, Zn, Hg, Cu, Si, and Mg, etc.) and in molecules (CH3Hg, Amino Acids) in the fields of geosciences, anthropology, contaminants, and the environment.

Leaders: David POINT and Klervia JAOUEN

Element cycles in the environment

  • Origin and cycle of mercury in the environment and marine and continental ecosystems.
  • Anthropogenic and climatic forcings on the isotopic signature of trace elements.
  • Origin and fate of greenhouse gases in aquatic environments.
  • Iron cycle in tropical and boreal environments.

Planet formation and evolution and its environments

  • Isotopic composition of planetary reservoirs.
  • Accretion processes and mechanisms of isotopic fractionation.
  • Chemical evolution of the Precambrian biosphere.
  • Oxygenation of the Earth’s surface and major nutrient cycles.

Anthropology, archaeological sciences.

  • Link between diet and biological and cultural evolution of our species.
  • New tracers and weaning age in prehistoric populations.
  • Traditional isotopes and geographical origins of humans and Neanderthals.
  • Tracing ancient metals.

Atomistic modeling of isotopic fractionations.

  • Isotopic messages of trace elements (Mg, Ba, Sr…) in carbonate minerals.
  • Modeling of liquids, ligand effects: isotopes of Ca and Zn in soil-plant systems.
  • Exploration of mechanisms occurring at the mineral-solution interface.
  • Fieldwork: observation and analysis of environmental archives.
  • Laboratory experimentation: mineral synthesis, isotopic exchange.
  • Modeling: atomistic, thermodynamic, geochemical.
  • Analytical innovations: ultratrace isotopic analyses, in situ preconcentration sensor, multidimensional isotopic analyses in specific compounds.

Scientific result

Why are large deposits of strategic metals associated with subduction zones?

Subduction zones are the most important places on Earth where matter is exchanged between the crust and the mantle. They are also the locations of the largest deposits of strategic […]

Scientific result

Algamarca gold deposit in Peru: News on its formation

With their partners from South American institutions, researchers from the Géosciences Environnement Toulouse laboratory (GET-OMP – CNES/CNRS/IRD/UT3) analyzed the fluids of the earth’s crust at the origin of the gold […]

Scientific dissemination

Capturing and storing CO2 to fight against global warming

On May 14, 2024, the Minister Delegate for Industry and Energy, Roland Lescure, announced that he wanted to launch 4 to 5 projects on CO2 storage in France from 2025 […]

Scientific result

Discovery of a large reservoir of hydrogen in an underground mine in Alabama

An international scientific team involving researchers from the Institut des sciences de la Terre (ISTerre* – CNRS/IRD/UGA/Univ. Gustave Eiffel/USMB) and GET has just discovered a reservoir of natural hydrogen in […]

Scientific result

Volcanic eruption: a new chronometer based on the diffusion of titanium in quartz

The process by which volcanic eruptions are triggered is still unpredictable. In order to assess the residence time of the magma in the chamber until the eruption, the international team, […]

Innovation

Synthetic minerals at the heart of the relationships between Imerys and the CNRS

With 170 sites employing more than 14,000 people in nearly 50 countries, Imerys is the world leader in minerals for the industry. The extraction and processing of these minerals pose […]

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