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Keywords from Image Description:
La Nature Percement du SaintGothard coupe du tunnel p. fr La Nature Percement du SaintGothard Coupe du tunnel Granit plus ou moins homogne Gneiss Calcaire cristallin micac Schistes micacs passant au gneiss alternant prs Andermatt avec des bancs de schistes noirs contenant des veinules calcaires Schistes micacs alternant