The 2019 Augustus Love Medal is awarded to Anne Davaille for innovative experiments and analysis in fluid mechanics, which have created a new understanding of convective regimes within the mantles of the Earth and other planets and of their magmatic systems.
Anne Davaille has made outstanding contributions to our understanding of convection in the Earth’s mantle and that of other planets. She is a leader in the development and application of laboratory experimental techniques and the application of experimental fluid dynamics to geodynamical problems. Using experimental techniques that are truly creative and novel, she has made fundamental advances in our understanding of thermal convection, in particular for convection in stratified systems. Her use of laboratory experiments has enabled her to address questions that are very difficult to treat computationally, yet are fundamental to understanding the evolution of the Earth and processes on other planets such as Venus. Among other contributions, she has studied the onset of small-scale convection beneath the stagnant lid of a layer with strongly temperature-dependent viscosity. She has detailed the existence of a doming regime in the fluid above a compositionally dense lower layer and was the first to demonstrate experimentally how a dense layer at the base of the mantle could stabilise thermal plumes over long geological periods. Her ground-breaking work on the effects associated with a dense basal layer has inspired a raft of computational studies on thermo-chemical plumes, and has provided new insights into how images derived from seismic tomography of the mantle should be interpreted. She was able to document mixing phenomena in convective systems over long time intervals and to explain the observations using simple scaling laws. Her recent experiments with fluids that possess a yield-strength rheology have opened new avenues of research into the interpretation of deep mantle processes. Her approach is based on a clear-cut logical design: innovative experiments that focus on a particular phenomenon are designed; results are analysed to obtain scaling laws based on a clear understanding of the fundamental conservation laws; planetary-scale phenomena are then interpreted based on the scaling laws. She introduced new techniques to accurately measure temperatures, compositions and velocities within the fluid mass. Such experiments have enabled us to better understand the physics of convection at scales that range from magma lakes to planetary interiors, particularly in regimes where 3D numerical experiments are difficult or even not possible with available resources. Where numerical techniques are possible her research has provided benchmarks against which these calculations can be calibrated. By using a rigorous approach to the analysis of innovative and well-designed experiments Anne Davaille has obtained a new understanding of convective processes that operate on a range of scales, from lava lakes to planetary mantles. Her research has led to new interpretations for the origin of hotspots, superswells and isotopic anomalies within the Earth’s mantle and the onset of subduction on Venus. For these reasons, she is a worthy recipient of the 2019 EGU Augustus Love Medal.