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[edit] = SEDEX and VMS/VHMS

Just a reminder not to confuse SEDEX with VMS deposits; most modern seafloor hydrothermal vents are related to VMS deposits , being related to hydrothermal systems developed above submarine volcanoes, spreading centers, etc, for instance the Marianas Trench, Tonga Arc[1], etc. See Neptune Minerals[2] for their so-called "SMS" or seafloor massive sulphide deposits.

While it is probably correct to correlate the exhalative phase of these deposits, because both tend to result in hydrothermal vents, black smokers, etc, the difference in source and transport is crucial; there are not very many VMS deposits which produce barite mantles, intraformational diaremes, and which are hosted predominantly within sedimentary sequences. In some cases, for nstance in China, these is evidence of SEDEX mineralisation occurring in lake beds within intracontinental rift grabens.

VMS deposits are in all cases correlated with eafloor volcanism, pelagic mud footwalls or volcanogenic footwalls, and lack the basin architecture neccessary for SEDEX to work. They are completely different.Rolinator 06:50, 16 October 2006 (UTC)