At the edge of a remote Mid-Atlantic ocean ridge, the Integrated Ocean Drilling Program (IODP) is using a  470-foot drill to take scientific samples of the ocean crust. Recent discoveries have shown that the deep ocean, once thought lifeless, is actually a hotbed for microbial ecosystems, collectively known as the “deep biosphere”. Using this drill, scientists are able to extract and analyze sediment cores to look at oxygen consumption and other factors that give insight into the survival of these microbial ecosystems. Findings using this drill have revealed that oxygen is “disappearing from seawater circulating through deep oceanic crust.” These findings seem to suggest that the microbes living within the oceanic crust, literally “buried alive”, are utilizing the oxygen in the deep ocean. Although this is just a first step, it provides concrete evidence for ideas that have been suspected for a long time. With this evidence, scientists can begin to quantify the metabolism of the deep biosphere, and to better understand how this ecosystem functions. This type of knowledge will, in turn, help us to better understand chemical cycling and the nature of life and existence on Earth. This could be big for the search for extraterrestrial life because it gives us a better understanding of biological and chemical processes here on Earth. The amount of life that is contained within the deep ocean crust is vast, and a better understanding of the inner workings of this ecosystem will only aid in the search for livable conditions outside of our planet, as well as life itself.

Related articles

• Breathing underwater: Evidence of microscopic life in oceanic crust (esciencenews.com)
• Breathing Underwater: Microbes in the Oceanic Crust  (astrobiology.com)