Claude Jaupart

Claude Jaupart (born 22 May 1953) is a French geophysicist and a member of the French Academy of Sciences (since December 2008).
Biography.
Professor of geophysics at the University of Paris-Diderot, and a researcher in physical volcanology, he is one of the world's leading specialists in natural hazards of geological origin. He was appointed a member of the Institute, French Academy of Sciences, Section of Universe Sciences. By a presidential decree of 12 January 2011, he succeeded Vincent Courtillot as head of the Institute of Earth Physics in Paris.
Claude Jaupart's work focuses on the thermal structure of continents, the characteristics of the internal movements of our planet responsible for continental drift and the modalities of volcanic eruptions.
Scientific work.
Six main themes..
        (1) Measurements of surface heat flux, calculation of the Earth's heat balance and its secular cooling rate.
        (2) Structure and thermal evolution of the crust and continental roots. Determination of the heat flux at the base of a continental root. Causes of the distribution in time and space of granitic massifs in a province. Mechanisms for stabilizing the continental crust. Consequences of the unstable nature of continental roots.
        (3) Convection in the Earth's mantle. How the movements and distribution of temperatures within the Earth are affected by the large variations in viscosity that prevail there and by the presence of continents.
        (4) Ascension of magmas and placement of magmatic reservoirs in the continental crust: at what depth and how magmatic reservoirs are formed, role played by the construction of a volcanic building on the surface.
        (5) Crystallization and differentiation of magmas: convective exchanges between the layers where crystallization occurs and the interior of a reservoir, competition between sedimentation/flotation of crystals and movements of the carrier magma.
        (6) Physics of volcanic eruptions: importance of gas leaks through the walls of a conduit, importance of coupling between flow at the surface and in an eruptive conduit, effects of compressibility on lava flows, effects of fragmentation and fragment size distribution (pumice and ash) on the behaviour of eruptive plumes in the atmosphere.