Rock Core Sediments: Calibrating a New Technique for the Investigation of Hydrothermal Activity at Ocean Ridges

Harvard University, Cambridge MA

Investigators

Abstract

Undersea hydrothermal systems at mid-ocean ridges are of central importance to the solid earth geochemical cycle, and also are the sites of large ore deposits of Cu and Zn and undersea oases of life. Finding these systems is very difficult, because they are hidden under many kilometers of water. Sediments from the ocean ridge system collect settling particles distributed through the water column by `plumes` of water rich in particles that rise from the hydrothermal vents. The distribution of metal enrichment in sediments may help to determine where hydrothermal vents occur, how long they have been present, and how large a hydrothermal system is involved. Because sediments can be collected easily from a ship on the sea surface, the sedimentary `halos` may allow an efficient assessment of the distribution and size of hydrothermal systems on a global basis. If so, then our understanding of the distribution of hydrothermal activity, and the scientific processes responsible for it, will be substantially enhanced. We propose to test the efficacy of this method using sediments, and to apply it to several first order problems relating to hydrothermal systems.