EarthRef.org Digital Archive (ERDA) -- Geochemical Fluxes and the Role of Seamounts in Ventilating the Oceanic Crust

Description
Ridge flank hydrothermal systems (RFHS) remove most of the convective heat loss from the oceanic crust. This heat loss and the associated fluid flow is almost completely confined to seamounts and guided by faults, because the permeability of basaltic basement is orders of magnitude greater than that of overlying sediment. The magnitude of this flow is the largest crustal fluid flux in the oceans, but it is only ~66% of the riverine water flux. Yet even a small chemical anomaly, resulting from water-rock interactions or from diffusive exchange with the overlying sediment, coupled with this amount of flow could result in a chemical flux that is important (defined as >10%) to global budgets. For example, the entire riverine influx of Mg could be deposited within the oceanic crust in the form of secondary clays (primarily smectites), given this vast flow of seawater through the crust and only a 0.3% decrease in the seawater concentration. Although the calculated thermal and fluid fluxes from RFHS are fairly well con-strained, chemical fluxes from RFHS are not well constrained because of the paucity of sites sampled to date. In this keynote presentation during the First SBN Workshop Geoffrey Wheat summarizes the recent studies that deal with geochemical fluxes from seamounts and their impact on global geochemical budgets.

Project -- Meetings and Workshops -- SBN Workshops
The goal of the Seamount Biogeosciences Network (SBN) is to bring together all the diverse science disciplines involved in seamount research, to communicate about and discuss seamount science, and to explore innovative ways to network amongst the diverse communities working on seamounts.