Sulfide structures build up as a result of precipitation and crystallization. Here you see several chimneys smoking on a sulfide structure called the Monolith vent site. This beautiful active sulfide structure is located on the Juan de Fuca Ridge, at 44°58' N & 130°14' W, to the south of the destination of this expedition.

(Dr. Michael Perfit, University of Florida, and NOAA VENTS program)

Black Smoker