Fig. 5
From: Preparation zones for large crustal earthquakes consequent on fault-valve action
a Mother Lode Au–quartz vein system hosted near Melones Fault, Coulterville, CA; inset at lower left shows Au–quartz veins boudinaged in steep reverse-sense ductile shear zone, Ferderber Mine, Val d’Or, Quebec. b Structural characteristics of fault-valve vein systems hosted on steep reverse faults (schematic and not-to-scale)