Fig. 14From: Deep hydrochemical section through the Central Alps: evolution of deep water in the continental upper crust and solute acquisition during water–rock-interaction along the Sedrun section of the Gotthard Base TunnelStreifen-gneiss mountains of the Gotthard-Massif (Piz Rondadura 3016 m). Inferred recharge area of water collected at tunnel level (500 m). Tunnel axis crosses beneath outcrops in the foreground at 2500 m (2000 m elevation difference)Back to article page