Geochemical species to monitor in a shale exploitation context

Summary
Review of geochemical species to monitor in a shale exploitation context. Aim: External Report on geochemical species that must be followed during shale exploitation. Scope: Put in evidence that a lot of geochemical species could be followed during shale exploitation but only a part of them have good interest to be followed, based on their specific geochemical properties which will be explained in details.