This proposal is for a Marie Curie EIF to work in the Isotope Geochemistry laboratory of the Department of Earth Sciences at the Swiss Federal Institute of Technology, ETH Zurich for 24 months. This project proposes the combined analysis of Ca, Mg, Si and Li isotope ratios in rivers and soils to better constrain the global biogeochemical cycles of these elements. Ca, Mg and Si are some of the most abundant elements on Earth and some of the most geologically important because of their role in biogeochemical cycles. The project has two aims: 1. To better constrain the processes affecting Ca, Mg and Si in the weathering environment, 2. To improve modelling of the global budgets of Ca and Mg. It is anticipated that the analyses and subsequent modelling will also be of interest to a variety of research areas from paleoclimatology, paleoceanography, to soil and agriculture sciences. The project will: 1. provide advanced training in multi-disciplinary research areas such as oceanic cycles, chemical alteration of the continents and geochemical modelling, diversifying present experience, and gain expertise in mass spectrometry in a world-class isotope geochemistry facility. 2. strengthen cooperation between research groups in the EU and Switzerland through transnational mobility.