ARE MORE PERMEABLE ROCKS ALWAYS IN FAVOR OF ECONOMIC ORE MINERALIZATION? INSIGHT FROM REACTIVE MASS TRANSPORT MODELLING (Invited Presentation)

Formation of most mineral deposits results from complicated interactions among fluid flow, heat and mass transport, and chemical reactions between difference phases. Geologists commonly view higher permeabilities of subsurface formations as a favorite condition for ore genesis since more permeable rocks enable more fluid to flow at a greater rate through source rocks and hence leach more minerals, and greater permeabilities also facilitate the minerals-bearing fluid to transport to proper locations for economic concentrations of metals.

To address the effect of rock permeabilities on the formation of mineral deposits, we developed a conceptualized 2-D model with consideration of unconformity-related uranium deposits as an example. Our reactive mass transport modelling using TOUGHREACT indicates that no economic ore mineralization can form under either very low or very high permeability conditions. There seems to be an optimal window of permeability for the formation of mineral deposits.