The LHE is a laboratory of environmental fluid mechanics whose research strives toward a better understanding of physical processes in the environment, with particular emphasis on the problems encountered in hydraulics and the study of geophysical flows. The field of research covered within Ancey's team includes the following topics: - Rheology & fluid dynamics of geophysical flow and the resulting hazards, with the objective of modeling natural hazards induced by water such as mudflows and avalanches. - Physics of bed load transport, aiming at better management of sediments in waterways Our major area of interest is the rheology of particle suspensions, mainly the natural suspensions involved in geophysical flows such as avalanches, mudflows, and stream transport of materials. Three major research orientations can be designated 1° Rheology of concentrated suspensions : we are particularly interested in the laws of very concentrated suspension behavior such as granular suspensions, investigating both the problem of determining adapted rheological laws and modeling free surface gravity flows. 2° The inverse problem :very often in rheology, stresses and strains cannot be measured directly; measures must first be taken on the macroscopic scale to then deduce the behavior on the microscopic level. This type of problem is most often within the domain of inverse problems. Our research aims most particularly to propose inverse determination methods either to adjust model coefficients or to deduce the mechanical behavior. 3° Particle entrainment in dilute turbulent suspensions: a major problem in geophysical flows is solid particle entrainment. We are mainly interested in understanding the erosion of a rough particle bed and modeling the phenomenon (Exner equation)