Iron oxide
The Moab Fault is characterized by patterns of iron oxide reduction that also suggest the fault acted as a conduit for mineralizing fluids. It is suggested that red sandstones adjacent to the Moab Fault were bleached by reducing fluids. Iron oxide reduction is concentrated within high permeability, well-connected sandstones and spatially associated with cemented veins – indicating that the reduction event coincided with vein formation, and thus with the final stages of faulting. Permeability along the fault may have been promoted by the highly anisotropic shaley gouge fabrics or by fault zone fractures.