Palm worms, limpets, and snails

A Vast Microbial Biosphere

The upper oceanic crust comprises the largest fractured aquifer on Earth. Fluid circulation within this aquifer provides heat and nutrients that sustains a vast microbial biosphere below the seafloor that is just beginning to be explored, but it that may rival that on the continents.

Episodes of Microbial Blooms

Fundamental questions exist concerning the depth and extent to which life may occur within the subseafloor and overlying sediments and the linkages between submarine plate tectonic and sedimentary process and this sub-seafloor biosphere. Unpredicted episodes such as magmatic eruptions at mid-ocean ridges increase nutrient (e.g., carbon dioxide) output and venting volume by as much as a factor of 100, resulting in extensive microbial blooms. Organisms sampled from high-temperature ecosystems at deep-sea hydrothermal vents have challenged our understanding of the physical and biochemical conditions under which life not only exists, but thrives.

Instrumenting the Seafloor

One of the most exciting prospects for the provision of high-bandwidth and power to the oceans is the advent of sophisticated seafloor observatories that incorporate instrumented drill holes deep within the seafloor and within the walls of black smoker chimneys. These systems will provide in situ time-series sampling of hydrothermal fluids and continuous measurement of temperature, gas chemistry, and pressure co-registered with the ability to sample microbial material within the context of this environmental data.

New Biotechnical Research

Studies of this vast biosphere are leading to new areas of biotechnical research that view subsurface organisms as resources for development of new pharmaceuticals important in fighting disease and infections and biocatalysts (enzymes) that are more efficient, thermally stable and cost-effective than synthetic catalysts important in material processing for industries.