SW Syoyo Vent



Latitude: 22.395oN                 Longitude: 142.755oE             Depth: 1450 m bsl

Southwest Syoyo hydrothermal vent is located in a caldera in an active Mariana submarine volcano (Baker et al., 2008).  SW Syoyo volcano lies in the rear arc of the Northern Seamount Province (Bloomer et al., 1989). No vent has been found but Resing et al. (2009, Table 4) report evidence of low levels of hydrothermal activity based on Light Scatter and Oxidation Reduction Potential (ORP) measurements using CTD rosette package. The plume is also seen in elevated Mn and 3He, for discrete water samples collected above the volcano (Resing et al., 2009). Because the vent has not yet been found, there is no information about biological community.

Table 1: Operations history for SW Syoyo vent

Ship/ Platform Operation Year References
TN-153 R/V T. G. Thompson EM 300 multibeam; CTD tow-yo; ORP 2003 February – March

Submarine Ring of Fire 2003

Table 2: Vent activity and host rocks

Activity and Host Rocks References
Activity Active Baker et al., 2008; Resing et al., 2009
Host Rocks Not found

Table 3: Plume Characteristics

Plume Anomalies References
ΔpH 0.004 Resing et al., 2009
Composition Small Mn and 3He Resing et al., 2009
TDMn (nM) 5 Resing et al., 2009
TDFe (nM) 0.27 Resing et al., 2009
Δ3He (fM) 2.8 Resing et al., 2009

* ΔpH – Measured relative to the regional background; Δ3He – Measured above the background.

Vent Biology: None known

Images: None known

Video Links: None known


  1. Baker, E. T., Embley, R. W., Walker, S. L., Resing, J. A., Lupton, J. E., Nakamura, K., de Ronde, C. E. J., Massoth, G. J., 2008. Hydrothermal activity and volcano distribution along the Mariana arc: Journal of Geophysical Research 113 (B8), 1-16.
  2. Bloomer, S. H., Stern, R. J., Fisk, E., Geschwind, C. H., 1989. Shoshonitic Volcanism in the Northern Mariana Arc. 1. Mineralogic and Major and Trace Element Characteristics. Journal of Geophysical Research 94 (B4), 4469-4496.
  3. Resing, J. A., Baker, E. T., Lupton, J. E., Walker, S. L., Butterfield, D. A., Massoth, G. J., Nakamura, K., 2009. Chemistry of hydrothermal plumes above submarine volcanoes of the Mariana Arc. Geochemistry, Geophysics, Geosystems 10 (2), 1-23.

Website References:

  1. Submarine Ring of Fire 2003 (accessed 02/16/2015)