Editing Ocean Drilling Program (section)

==== Presence and Activities of Bacterial Populations ====
Evidence from the ODP contradicted expectations that biological activity is more heavily concentrated near Earth's surface.<ref name=":4" /> Large populations were discovered, which added around 10% to global [[biomass]] estimates.<ref name=":4" /> The abundance of bacterial populations decreased with depth, and deeper bacteria had slower growth rates.<ref name=":4" /> Despite this overall trend, there were certain geochemical conditions and [[Thermogenics|thermogenic]] processes that allowed bacterial populations to thrive at depth.<ref name=":4" /> For example, near gas hydrate deposits, rates of methane oxidation increased due to the abundance of organic carbon present.<ref name=":0" /><ref name=":4" /> Additionally, the rates of [[methanogenesis]] and acetate [[metabolism]] increased in bacteria in the subsurface compared to those near the surface.<ref name=":4" />