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Project Progress

Organic Synthesis at High Temperatures (dm)

Our overall goal in this research is to explore the potential for abiotic synthesis of organic molecules important to the origin of life under geologically realistic conditions of pressure, temperature and chemical composition. To this end we have detailed how volcanic diking-eruptive events on the seafloor can lead to short-term high levels of carbon dioxide and hydrogen gases. We then determined experimentally that those gases and water react at typical seafloor hydrothermal conditions to form methanol, a significant organic precursor molecule, in the presence of the mineral magnetite. Building on kinetic studies of the conversion of smectite clay to illite, we have begun experiments to follow the conversion of methanol to more complex organic molecules in the presence of smectite/illite clays.

We constructed and tested a new high-pressure reactor to safely study organic synthesis reactions in sulfide systems. The operating parameters for this system were determined using thermodynamic calculations as a guide.

The internal structure of sulfide chimneys in seafloor systems may provide sites for concentrating pre-biotic organic molecules. The recent collection of a large, living chimney has provided excellent samples to examine microporosity using synchrotron X-ray tomography, and preliminary results have been reported showing porosity down to the limit of resolution of the technique, about ten micrometers.

We have established a collaboration to develop analytical techniques based on optical fiber probes to allow chemical analysis of small volumes in experimental apparatus for organic synthesis and in natural environments at hydrothermal conditions.

These accomplishments were included in our proposed goals for the third year. However, we have not made as much progress on the artificial seafloor hydrothermal system experiments as planned due to the need to redesign and construct portions of the system. We also expended a significant effort in improving our techniques for analyzing organics in aqueous solutions.