PMS, polymetallic massive sulfides
Notes on Vent Field Description:
Fig. 13 in Francheteau and Ballard (1983) shows vents from 20 06' to 20 09'S; small vent fields with active sulfide deposits in the axial rift; Renard et al. (1985) say that this is a "non-rifted segment"; Francheteau and Ballard: "a continuous series of active hydrothermal vent fields (Fig. 13) of both the Galapagos-type (dense animal communities) and the East Pacific Rise 21°N-type (animal communities and sulfide deposits)"
Notes Relevant to Biology:
Francheteau and Ballard (1983): "Clams, anemones, crustaceans (both Brachyuran and Galatheid types), starfish and three types of vent fish have been identified in the ANGUS photographs. Additionally, large gastropods (whelks) and what appear to be large hemichordates (acorn worms) are present in abundance."
Year and How Discovered (if active, visual confirmation is listed first):
1981 Angus camera tow; 1984 submersible Cyana
Discovery References (text):
Ballard, et al. (1981) Geology and high temperature hydrothermal circulation of ultra-fast spreading ridge: East Pacific Rise at 20°S, EOS 62, 912
Francheteau and Ballard, Earth Planet. Sci. Lett. 64, 93-116, 1983, The East Pacific Rise near 21°N, 13°N and 20°S: inferences for along-strike variability of axial processes of the Mid-Ocean Ridge
Renard, V. et al., Earth Planet. Sci. Lett., 75, 339-353, 1985, Submersible observations at the axis of the ultra-fast-spreading East Pacific Rise (17°30' to 21°30'S).
Other References (text):
Klinkhammer and Hudson, Earth Planet. Sci. Lett. 79, 241-249, 1986, Dispersal patterns for hydrothermal plumes in the South Pacific using manganese as a tracer, doi:10.1016/0012-821X(86)90182-2.