Skip to Main Content


Calculations based on the thermochemical stabilities of the ore and gangue minerals suggest that appreciable quantities of sulfate ion and methane should not coexist in an ore-forming environment. However, highly suggestive but unfortunately inconclusive observations do suggest that both methane and sulfate are present in amounts that are impossible to reconcile with the calculations based on the assumption of equilibrium. This paradox is tentatively interpreted to show that the ores were precipitated from solutions in which the heavy metals were carried as complex chloride ions whereas the sulfur exists metastably as sulfate ion. The sulfides were precipitated when the sulfate was reduced nonbiogenically to sulfide by methane or associated organic matter that was carried in, or encountered by, the ore-bearing aqueous fluid.

You do not currently have access to this chapter.

Figures & Tables





Citing Books via

Close Modal
This Feature Is Available To Subscribers Only

Sign In or Create an Account

Close Modal
Close Modal