A Dynamic Hydrothermal Experimental System

A unique dynamic hydrothermal system has been built to study the alteration reactions between seawater and basalt in the temperature range of 0 to180\degC. The purpose of the system was to approximate in the laboratory the type of geochemical reactions which would occur in a submarine hydrothermal circulation of seawater at active mid-ocean spreading centres. A total hydrostatic pressure of at least 1000 bars (\pm 10bars) and a temperature difference of0\degC to180\degC could be established between interconnected reaction chambers containing seawater and basalt. Basalt/seawater ratios as great (or greater) than 1:50 where used. The use of a large volume reservoir of seawater allowed a continuous flow of fresh seawater through the basalt with the ability to sample the seawater continuously without disturbing the temperature or pressure of the experimental system.