Geocheminar winter-2016

Biogeochemical limits to subsurface habitability

Microorganisms have been found in just about every subsurface environment where scientists have looked. Little is known about what reactions these organisms are catalyzing or at what rate they are active. As a result, the influence that microorganisms have driving global element cycles in a significant fraction of Earth’s habitable volume is poorly understood. In this presentation, I will describe recent experimental and computational work that is designed to quantify what microorganisms are doing and how fast they’re doing it in energy-limited, subsurface habitats. In particular, I’ll present some modeling work that is geared towards quantifying what constitutes a habitable environment in marine sediments, and show the results of some nanocalorimetric microbial growth experiments.