Although no active gas bubbling was observed during Dive 19, the dense patches of live Bathymodiolus childressi mussels and associated bacterial mats are indicators of fluid seepage. Such ecosystems rely on methane or hydrogen sulfide produced during the bacterial breakdown of methane for their metabolic processes, meaning that an active methane system must be present below the seafloor. Red laser dots are separated by 10 centimeters (3.94 inches).