Check out our new publication about sulfur cycling in a deep biosphere coal bed.
Microbial sulfate reduction potential in coal-bearing sediments down to ~2.5 km below the seafloor off Shimokita Peninsula, Japan, Clemens Glombitza, Rishi Ram Adhikari, Natascha Riedinger, William Patrick Gilhooly III, Kai-Uwe Hinrichs, Fumio Inagaki, Frontiers in Microbiology, 2015
http://journal.frontiersin.org/article/10.3389/fmicb.2016.01576/full