Maug Vent



Latitude: 20.021οN                  Longitude: 145.222οE             Depth: 54 m bsl

Maug is an extinct volcano located in the Central Seamount Province (Bloomer et al., 1989). Maug consists of three islands arranged in a circular pattern around a caldera in which sits a resurgent dome that almost reaches sealevel (Submarine Ring of Fire, 2003). ROV dives found several diffuse vents clustered on the ENE quadrant of the central cone (Embley et al., 2007). Fluids released from weak vents around the central dome show elevated 3He levels and suggest that the central dome is actively degassing. These fluids are also enriched in CO2, TDMn, TDFe, pFe, and pMn (Resing et al., 2009). Maug is one of the few places on earth where photosynthetic and chemosynthetic life coexist. This unique community is composed of Bacteria, Fish, Soft corals, Gorgonians, Brittle stars, Worms and Mussels (Pala, 2009).

Table 1: Operations history for Maug vent

Ship/ Platform Operation Year

Dive Number


TN-153 R/V T. G. Thompson

EM 300 multibeam

2003 February – March

Not found

Submarine Ring of Fire 2003

TN-167 R/V T. G. Thompson

CTD Verical cast; ROPOS

2004 March- April

R789, R790

Submarine Ring of Fire 2004

Table 2: Vent activity and host rocks
Activity and host rocks References
Activity Active Baker et al., 2008
Host Rocks



Embley et al., 2007

Woodhead., 1989

Table 3: Vent fluid characteristics

Vent Fluids


Temperature (οC)

60 οC (at 30 feet deep)

Low T (<100 οC)

Pala., 2009

Embley et al., 2007

pH 6.07 Pala., 2009
ΔpH -0.17 Resing et al., 2009

Large concentrations of methane, total (particulate plus dissolved) Fe, and total Mn.

CO2 and alkalinity

Submarine Ring of Fire 2003

Resing et al., 2009

CO2 (mM) Not found
ΔCO2 (mM) 119 Resing et al., 2009
H2 (mM) Not found
Particulate Fe (nmol/kg) 1238 Resing et al., 2009
TDMn (nM) 98 Resing et al., 2009
TDFe (nM) 700 Resing et al., 2009
Δ3He (fM) 12.8 Resing et al., 2009
3He (μM) Not found
CH4 (nM) 90

Resing et al., 2009

* ΔpH, ΔCO2 – Measured relative to the regional background; Δ3He – Measured above the background.

Table 4: Vent Biology

General name Phylum References
Bacteria Bacteria Pala., 2009
Fish Chordata Pala., 2009
Soft corals Cnidaria Pala., 2009
Gorgonians Cnidaria Pala., 2009
Brittle stars Echinodermata Pala., 2009
Worms Pala., 2009
Mussels Mollusca Pala., 2009


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., Smoot, N. C., 1989. Physical volcanology of the submarine Mariana and Volcano arcs. Bull Volc 51, 210-224.
  3. Embley, R. W., Baker, E. T., Butterfield, D. A., Chadwick, W. W. Jr., Lupton, J. E., Resing, J. A., de Ronde, C. E. J., Nakamura, K., Tunnicliffe, V., Dower, J. F., Merle, S. G., 2007. Exploring the submarine ring of fire: Mariana Arc- Western Pacific, Oceanography 20, 68–79.
  4. Pala, C., 2009. The Pacific Ocean’s Acidification. Environmental Science and Technology 43, 6451–6452.
  5. 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 11/19/2015)
  1. Submarine Ring of Fire 2004 (accessed 11/19/2015)

Cruise Reports:

  1. Submarine Ring of Fire 2003 (accessed 11/19/2015)
  2. Submarine Ring of Fire 2004 (accessed 11/19/2015)