As the biosphere has delved
ever deeper into the ocean’s sediments, evidence has also come to
light for a
biosphere within the basaltic crust of the ocean. Though basalt
is an igneous rock, it underlies ocean sediments, and interactions with
the basalt are an important part of ocean dynamics.Weathering
textures on basalts recovered from dredging off of ocean ridges are
unlike those caused by chemical weathering,
possibly indicating microbial activity (eg. Fisk et al. 1998).These weathering zones have been found to contain elevated
amounts of
carbon, phosphorous, nitrogen, and traces of nucleic acid.Cell shaped bodies have been observed in the
weathering structures using an electron microscope.The cells are found in channels utilized by
hydrothermal fluids and in reaction rims (Fisk et al. 1998).
Living cells photographed in a fracture zone in 2.5 Ma
basalt, using an electron microscope. (Thorseth et al. 2003).
Cell-like bodies observed in 145 Ma basalt from the Antarctic
Discordance. Scale bar is 10 micrometers (Fisk et al. 1998).
