The present project is dedicated to the characterization of chemical exchanges within water-rich bodies including icy moons of Jupiter and Saturn as well as exoplanets that may be discovered in a near future. Recent spacecraft missions, Galileo (1996-2003) and Cassini-Huygens (2004-today), have revealed that complex chemical exchanges between their warm silicate inner core and their water-rich outer layer have occur on Enceladus, Europa and Titan. Similar exchange processes are also likely to occur within water-rich planets outside our Solar System. Here I propose to combine experimental investigations and numerical modelling to quantify the degree of interaction between seafloors, oceans, ice shells, and surfaces, atmospheres of water-rich worlds. This innovative approach will provide the first complete description of exchange processes on water-rich bodies and will constrain the conditions for which such water-rich environments are favourable for the development of life.The proposed sophisticated modeling of interactions between the interior and surface will provide precious tools for the interpretation of Galileo/Cassini observations and will significantly improve our current understanding of planetary processes. The output of these numerical simulations will also help for the definition of measurements that should be done by future exploration missions (EJSM and TSSM) in order to constrain the composition and size of icy moon s ocean.The detection of water-rich around other stars is within our reach. When the first detections of a water-rich planet and the first identification of atmospheric components will occur, my proposed modelling efforts will provide a theoretical framework for the data interpretation in term of physical and chemical conditions of their ocean and atmosphere. This will provide key constraints to define if a detected planet outside our Solar System is a good candidate for harbouring life.