Biogeological mineralization in deep-sea hydrothermal deposits.

Oriented drill cores retrieved from active massive sulfide edifices at the Endeavour Segment of the Juan de Fuca Ridge contain an abundance of fossilized tube structures associated with vestimentiferan and annelid worms. The petrological evolution of these biogeological structures and their presence deep inside the edifice walls demonstrate that an initial, worm-mediated texture directly affects the subsequent steps of inorganic precipitation, wall infilling, and outward growth of these black smoker deposits. The presence of fossilized structures in hydrothermal discharge sites that are 2 kilometers apart and their similarity to structures observed in other modern and ancient deposits suggest that these biogeological processes are general phenomena.