Cataclasite dike, Sierra de Hualfin, northwestern Argentina


Pilar Garcia studied this area as the focus of her PhD dissertation at The University of Arizona.  I visited her in her field area back in 1999, to walk/hike/climb the geology with her.  On one of the traverses we made we encountered these features.   

Age & Formation
A product of faulting in the Tertiary, probably in the Miocene, ~20 Ma.