Broadly defined, geobiology is an interdisciplinary field of scientific research that explores interactions between the biosphere and the lithosphere and/or the atmosphere.[1]
Investigators from numerous fields are involved in geobiologic research, including, but not limited to, such disciplines as: paleontology, paleobiology, microbiology, mineralogy, biochemistry, sedimentology, genetics, physiology, geochemistry (organic and inorganic), and atmospheric science. One major subdiscipline of geobiology is geomicrobiology, an area of study that focuses on investigating the interactions between microbes and minerals. Another related area of research is astrobiology, an interdisciplinary field that uses a combination of geobiological and planetary science data to establish a context for the search for life on other planets.
The study also focuses on biosphere/geosphere/atmosphere interactions throughout Earth's history, as preserved in the sedimentary rock record. One example of such an interaction is the Archean era introduction of oxygen into the atmosphere by photosynthetic bacteria. This oxygenation of Earth's primoidial atmosphere (the so-called oxygen catastrophe) may have resulted in the precipitation of banded-iron rock formations.
One example of geobiological research in a modern context is the study of bacteria that "breathe" metals such as manganese and uranium. These organisms use metals as terminal electron acceptors in the same way that animals use oxygen. These processes hold promise as tools for environmental bioremediation.