GEOCHIMIE: TRAÇAGE ISOTOPIQUE, MINERAL, ET ÉLEMENTAIRE
GEOCHEMISTRY: ISOTOPIC, MINERAL AND ELEMENT TRACING
Cosmochemistry is the study of the chemical composition and evolution of the universe. Objects in our solar system (the Sun, the planets and their satellites, asteroids and comets, and the smaller samples (e.g. meteorites, returned lunar samples) derived from them) tend to be focused upon.
At ULB we use short-lived isotope (e.g. 146Sm-142Nd, 26Al-26Mg) as well as stable isotope (e.g. Ca) systems to understand the formation of the solar system and the evolution of the terrestrial planets and their satellites.
Understanding the processes that changed the molten early Earth to an Earth with atmosphere-ocean systems and plate tectonics similar to that we are familiar with today is essential for understanding planetary habitability. Cosmochemistry is a very interdisciplinary field that draws on knowledge from a wide range of disciplines, such as planetary astronomy, geology, geochemistry, and geophysics.
For more details, please see Vinciane Debaille's profile.
Geodynamics is generally concerned with processes that move materials throughout the Earth. It applies physics, chemistry and mathematics to the understanding of how mantle convection leads to plate tectonics and geologic phenomena such as seafloor spreading, mountain building, volcanoes, earthquakes, faulting, and so on. It also attempts to probe the internal activity by measuring magnetic fields, gravity, and seismic waves, as well as the mineralogy of rocks and their isotopic composition. At ULB our focus is specifically on:
Early Earth evolution: Elemental and isotopic (radiogenic and non-traditional stable) abundances are investigated in meteorites and Archean terrestrial rocks in order to understand, define, and describe early Earth formation and early crustal evolution with a particular focus on mantle dynamics.
Mantle Plumes: Ultrabasic and basic xenoliths, together with lavas, from Large Igneous Provinces (e.g. Kerguelen, Cape Verde hot spots) are investigated in order to study mantle plume dynamics and geochemical signatures.
For more details, please see Vinciane Debaille's or Nadine Mattielli's profiles.
Environmental geochemistry focuses on the chemical processes that couple the lithosphere, hydrosphere, biosphere, atmosphere, and anthroposphere. It is principally concerned with the sources, dispersion and distribution of chemical elements and gases in the surface environment, their chemical forms and pathways into water, agricultural crops and animals, and their effects on the health of plants, animals and humans.
Research at ULB is focused primarily on metals (Zn, Cu, Fe, Cd, ...) in the geosphere and anthroposphere (i.e. natural (ocean, atmosphere) or contaminated environments of mining and smelting areas, plant-soil systems, estuaries, etc.) with emphasis on non-traditional stable isotopes in tracing the processes that control metal biogeochemical cycling.
For more details, please see Nadine Mattielli's profile.
Volcanoes are formed when magma from within the Earth's upper mantle works its way to the surface. As magma rises within the Earth's crust, it often interacts with the local water table to produce hydrothermal systems, areas of heated groundwater that begin to cycle through the region and alter the chemistry of local rock formations as well as manifest themselves on the surface in lakes, and as geysers, fumaroles, and hot springs.
At ULB, studies of the chemical and isotopic compositions of volcanic lakes and thermal springs are carried out in the field (e.g. Indonesia and Philippines) to improve the understanding of the hydrothermal system dynamics associated with volcanic eruption forecasting.
For more details, please see Alain Bernard's personal website.