What is your role in Extreme 2002?

My research focuses on chemical partitioning between fluids and solids in geochemical systems and on micro-chemical environments at mineral surfaces that support microbial habitats. Deep-sea hydrothermal systems offer a unique environment in which to study the interplay between abiotic geochemical reactions and microbiological processes at rapidly changing physical and chemical interfaces.

We are investigating how microbial colonization is influenced by the dynamic thermochemical gradients and variable mineral and fluid chemistry of deep-sea hydrothermal vents and, in turn, how the presence of microorganisms influences the local geochemistry. We are examining young seafloor hydrothermal chimneys because they represent one of the few environments on Earth that are known to evolve rapidly from strictly abiotic conditions to complex microbial communities in a short time period (days to weeks).

Our goals on this cruise are to create artificial chimneys on seafloor vents and to determine if or when microhabitats became suitable for life by studying their interior chemistry, mineralogy, and physical structure and looking for evidence of microbial colonization. This data, combined with temperature and fluid measurements taken on the seafloor, will allow us to reconstruct the local geochemistry and mineralogy associated with conditions that make this extreme environment habitable for microorganisms.

My background is in aqueous and environmental geochemistry, mostly of surface rather than deep-sea environments. I became interested in the fascinating biogeochemistry of seafloor hydrothermal chimneys several years ago and participated in my first research cruise last year with Extreme 2001.