Geochemical fluxes of gases and elements from hydrothermal vents

The overall total mass flux from the world s deep-sea hydrothermal vents is estimated to be on the same order of magnitude as estimates of the flux from the Amazon river, or about 2% of global river discharge (Elderfield Schultz, 1996 Scott, 1997). Hydrothermal vents can have globally significant mass fluxes that are especially important for their effect on the budgets of elements 

Compositional data and river fluxes from Kadko etal. (1994) with modifications based on Edmond etal. (1995) and Scott (1997). Hydrothermal fluxes were calculated assuming a fluid flux of 3.70 x 1013 kg y-1 (Mottl, 2002). Value of magnesium flux from the oceans to the crust is from Mottl (2002). 

Not all elements dissolved in hydrothermal fluids end up in the ocean. For example, Fe and Mn are generally deposited as sulphides or oxides in chimneys 

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