9618179 Seewald Although it is known that much of the organic matter in the marine environment is generated at high temperature and that organic species play an important role in a variety of physical, chemical, and biological processes in the seawater, sediments, and vent systems, virtually nothing is known about the high- temperature and high-pressure stability or rates of production and reaction of such organic compounds. One reason for this lack of understanding is the relative inaccessibility of marine hydrothermal systems to detailed organic chemical analysis in the field. In this study the principal investigator will get around this limitation by studying stability relationships of several types of organic compounds (especially aromatics) and the reversibility of their reactions in a laboratory especially designed for high-pressure, high-temperature work. The principal investigator expects that these studies will greatly increase our current understanding of the processes and conditions responsible for the occurrence of these substances in marine hydrothermal systems. ***
