The Behavior of Rare Earth Elements in Hydrothermal Systems: An Experimental Investigation

Woods Hole Oceanographic Institution, Woods Hole MA

Investigators

Abstract

The goal of this proposed study is to obtain data on the partitioning of rare earth elements (REE) between minerals and aqueous fluids under conditions like those existing in active hydrothermal systems. This will allow a more quantitative evaluation of hypotheses regarding mineral reactions in the so-called "reaction zone" of active systems. With a variety of starting materials and conditions, the experiments will help understand REE partitioning during alteration of plagioclase and clinopyroxene, the main REE- carrying minerals in basalt and diabase. In addition, experiments will be done to evaluate the effect of anhydrite and barite precipitation on the REE patterns of hydrothermal fluids. This study will specifically test the hypothesis that the REE patterns of hydrothermal fluids are due mostly to the alteration of plagioclase.