Dr Charles Le Losq

Ph.D. Geophysics (IPGP), Master (IPGP) and Licence (U. Poitiers)
Research Fellow

I became passionate about volcanology when I was a student at the University of Poitiers in France. I moved at the Institut de Physique du Globe de Paris (France) to study geochemistry, volcanology and igneous processes. I studied how the chemical composition of aluminosilicate magmas affects their viscosity under the supervision of Daniel Neuville (DR1 CNRS-IPGP) during my Master internship and my Ph.D. thesis. Then, to learn more about volatile elements and to expand my experimental knowledge and abilities, I moved to Washington D.C. (U.S.A.) where I had the opportunity to become a PostDoctoral Fellow at the Geophysical Laboratory. In collaboration with Bjorn Mysen (Senior Scientist) and George Cody (Acting Director), I studied how water interacts with the molecular structure of silicate melts. I presently occupy a Research Fellow position at the Research School of Earth Sciences, The Australian National University, in Canberra. Working under the supervision of Professor Hugh St.C. O’Neill (ARC Laureate Fellow), I am involved in several collaborative projects with the Experimental Petrology group about water, minerals and magmas in the Earth. In addition to those themes, I also am interested in computer programming, optimisation and machine learning, and their use to solve problems related to volcanic systems and the Earth.

Research interests

My current projects focus on:

- "Hydroxylation spectroscopy" of olivine: decorating the existing point defects in olivine crystals may allow us to know what were the last equilibration conditions of the crystal. This could be used as a tool for unravelling the geologic history of mantle olivine, and, hence, it may be important to assess problems ranging from the determination of the conditions characterising the upper mantle (and their possible heterogeneity) to understanding the timescale of volcanic eruptions carrying olivine crystals.

-Water in silicate melts, and how it affects the structure and properties of silicate melts. As the latter transport water from the upper mantle and the crust to the Earth surface, and as dissolved water profoundly affects their physical properties, this is important to assess problems from the transfers of heat and matter in the Earth mantle and crust to the dynamic of volcanic eruptions.

- Rheology of magmas, and development of viscosity models: viscosity models for silicate melts based on structural and thermodynamic knowledge may allow us to i) rationalise past eruptive dynamic of volcanoes in regard of the rheology of their magma, and help predict possible future eruptive scenarios; ii) help constraining fluid dynamic models of volcanic eruptions; iii) help us understand the planetary differentiation process, as they can be used to assess the dynamic of possible large-scale magma oceans at surface and/or at depth of primitive planets, in particular the proto-Earth.

- Using Raman and IR spectroscopy to study molecular structure and processes in silicate materials. I have a particular interest in using Raman spectroscopy to measure the water content of very small, challenging melt inclusions. Furthermore, I also want to understand how the structure of silicate melts change with temperature, chemical composition and pressure in order to link that to the previous point.