Fig. 5

Field photographs of the GBF zone. (Locations given in Swiss national grid format). a 50 cm thick core breccia lining recessive lineament on major Sidelhorn fault linkage (2667245, 1156454). b Looking north at a late fault plane (dip direction 190°, dip of 80°) in the GBF core with slickensides dipping ca. 30° W (2667429, 1156426). c Microcrystalline quartz-cemented breccia with granitic clasts lining a recessive lineament (ca. 2666670, 1156400). d Fault surface (dip direction 190°, dip of 70°) in secondary breccia with 17° W dipping slickensides (2666422, 1156263). e Typical coarse quartz-sulphide mineralisation at the north ridge of Sidelhorn (2667170, 1156470). f Irregularly shaped celadonitic chert infill between Totensee and Gletsch (2670294, 1157235). g 3 m wide mineralised damage zone around 10 cm thick secondary fault, ca. 10 m from the GBF core at the north ridge of Sidelhorn (2667155, 1156464). h Dilatant jogs/fractures with quartz-sulphide coatings, 5 m from the GBF core on the NW slopes of the Sidelhorn (2667121, 1156479)