Sampling an erupting volcano at 550-m depth, discovering roiling pools of liquid sulfur at 400-m depth, watching tropical fish swimming amid fields of black smoker vents, and encountering a blizzard of liquid carbon dioxide globules rising from fractured lava flows at 1600-m depth all sound like wishful thinking or scenes from a science fiction movie. But, we had the good fortune to observe these and other previously unseen phenomena between 2004 and 2006 during a series of expeditions to the Mariana arc in the western Pacific. We describe here several of the most interesting sites, along with their geologic and oceanographic contexts.

Embley, R.W., E.T. Baker, D.A. Butterfield, W.W. Chadwick Jr., J.E. Lupton, J.A. Resing, C.E.J. de Ronde, K.-I. Nakamura, V. Tunnicliffe, J.F. Dower, and S.G. Merle. 2007. Exploring the submarine ring of fire: Mariana Arc - Western Pacific. Oceanography 20(4):68–79, https://doi.org/10.5670/oceanog.2007.07.

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