title: Detection of low-temperature hydrothermal fluxes by seawater Mg and Ca anomalies
abstract: Geochemical fluxes into and out of the ocean control its chemical composition. Measurements of the magnesium (Mg) content of seawater, an assumed "conservative" element in the ocean, reveal mid-depth Mg depletions in the vicinity of the East Pacific Rise. The magnitude of the anomalies suggests that fluxes associated with the low-temperature circulation of seawater through axial mid-ocean ridge systems are much larger than the high-temperature axial component. A higher total axial hydrothermal flux provides a mechanism that simultaneously satisfies the mass balance requirement of several major seawater constituents.
authors.affiliation: Geological Sciences Department, Box 35-1310, University of Washington, Seattle, WA 98195-1310, USA.
authors.lastname: de Villiers S
authors.initials: BK
authors.lastname: Nelson