Criteria for Recognit

Extension and Rifting(McKenzie and Bickle, 1988)(Franklin et al., 2005)•Heat: upwelling mantle causes increase in heat flux and upward warping of isotherms – the heatflux to drive volcanism and at higher crustal levels circulation of evolved seawater•Extension: provides extensive,vertical fluid conduits that are reactivated to focus dike-sillemplacement, volcanism, subsidence, and the upflow of hydrothermal fluid (e.g., synvolcanicstructures), but also provide the permeability needed for deep penetrating evolved seawater toleach metals within rifts (+/-magmatic fluid component)Thermal Corridor: High heat flow, plutonism, high-temperature volcanism, sedimentation, andsubsidence focused in time and space - essential to the formation of high temperaturehydrothermal systems responsible for the formation of VMS deposits