Microbial acetogenesis as a source of organic acids in ancient Atlantic Coastal Plain sediments

Field and laboratory evidence shows that deeply buried (90–888 m) fine-grained sediments of the Atlantic Coastal Plain contain viable acetogenic microorganisms, and that these microorganisms actively produce organic acids. Concentrations of formate, acetate, and propionate in pore waters extracted from fine-grained sediments ranged from 50 μM to 5 mM and were much higher than in adjacent pore waters associated with sandy sediments (