NW Rota-1 Vent



Latitude: 14.600οN                  Longitude: 144.775οE             Depth: 527 m bsl

NW Rota-1 is an active submarine arc volcano in the rear arc region of the S Seamount Province and shows a steep-sided cone morphology (Chadwick et al., 2008). Volcanic activity was first detected in 2004 (Embley et al., 2006) and repeat visits in 2005 and 2006 confirmed that it was in a continuous state of eruption (Chadwick et al., 2008; Embley et al., 2006). Venting at Brimstone pit was characterized by pulsating plume with droplets of molten sulfur, basaltic ash, lapilli and occasional bombs (>15 cm) falling from the plume after being ejected from the pit (Embley et al., 2006a). Resing et al., (2007) state that this vent discharges sulfuric acid-rich fluids and are also enriched in dissolved and particulate species of metals and gasses such as Fe, Mn and CO2 respectively. The venting began as degassing magma associated with eruption at Brimstone pit.  Later visits found venting to be either in the form of CO2 rich gas bubbles or liquid CO2 droplets (Lupton et al., 2008).   Some biological communities such as shrimp including two species Alvinocaris sp.M and Opaepele loihi (Stevens et al., 2008) and a type of Proteobacteria called Epsilonproteobacteria (Huber et al., 2010) dominate the NW Rota-1 communities.

Table 1: Operations history for NW Rota 1 vent

Ship/ Platform Operation Year Dive Number References
MGLN02MV R/V Melville SeaBeam 2000 Multibeam 2006 April- May J2-186 to J2-189, J2-191, J2-192 Submarine Ring of Fire, 2006

Woods Hole Oceanographic Institution: ROV JASON/MEDEA: Operations Summary (note: click “Files- operations summary”)

RR1413 R/V Roger Revelle/ Jason Multibeam re-survey, CTD 2014 J2-800 Submarine Ring of Fire 2014-Ironman
NT 0517 R/V Natsushima/  Hyper-dolphin Not found 2005 October HPD#0480 HPD#0481



NT05-17 cruise report
NT 10-13 Natsushima Leg.2/ Hyper-dolphin Not found 2010 July HPD#1161 NT10-13 leg2 cruise report
TN-232 R/V Thompson/ ROV Jason-2 Not found 2009 April J2-396 to J2-412 Woods Hole Oceanographic Institution: ROV JASON/MEDEA: Operations Summary (note: click “Files- operations summary”)
R/V Kilo Moana/ ROV Jason-2 Not found 2010 March J2-487 to J2-495 Woods Hole Oceanographic Institution: ROV JASON/MEDEA: Operations Summary (note: click “Files- operations summary”)
TN-167 R/V T. G. Thompson/ ROPOS CTD tow-yo, CTD vertical cast, EM 300 2004 March- April R782-R784, R786 Submarine Ring of Fire 2004

Table 2: Vent activity and host rocks

Activity and host rocks References
Activity Active volcano

Continuous state of eruption through 2004-2006

Embley et al., 2006; Chadwick et al., 2008; Resing et al., 2009; Dziak et al., 2012
Host Rocks Basalt, basaltic andesite and andesite Stern et al., 2008

Table 3: Vent fluids

Vent Fluids References
Temperature (οC) Brimstone pit 25-120

High T


Lupton et al.,2008

Resing et al., 2009

Embley et al., 2009

Iceberg 53.8 Huber et al., 2010
Sandy Saddle 35.6 Huber et al., 2010
Fault Shrimp 25.9 Huber et al., 2010
Scarp Top 17.6 Huber et al., 2010
pH Brimstone pit



Huber et al., 2010

Lupton et al.,2008

Iceberg 3.75 Huber et al., 2010
Sandy Saddle 2.62 Huber et al., 2010
Fault Shrimp 5.25 Huber et al., 2010
Scarp Top 5.09 Huber et al., 2010
ΔpH -0.730 Resing et al., 2009
CO2 (mM) 7.63-93.5 Lupton et al., 2008
ΔCO2 (mM) 40 Resing et al., 2009
H2 (mM) 0.0001-12.6 Lupton et al., 2008

Focused flow rich in Al, S, Si, CO2, Fe, Mn, and 3He. Diffuse flow rich in Fe, Mn, CO2, and 3He but without Al, S, and Si.

Resing et al., 2007
Particulate Fe (nmol/kg) 2052 Resing et al., 2007
TDMn (nM) 150 Resing et al., 2007
TDFe (nM) 2300 Resing et al., 2007
Δ3He (fM) 15.3 Resing et al., 2007
3He (μM) 0.0368-38.11 Lupton et al., 2008
CH4 (mM) 0.00002-0.0099 Lupton et al., 2008

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

Table 4: Vent biology

General name Phylum Class/Order Family Genus/Species References
Bacteria Proteobactera Epsilonproteobacteria Huber et al., 2010
Shrimp Arthropoda Decapoda Alvinocaridae Alvinocaris sp.M Stevens et al., 2008
Shrimp Arthropoda Decapoda Alvinocaridae Opaepele loihi Stevens et al., 2008


  1. A degassing event at Brimstone Pit at NW Rota-1.
  2. Shrimp at NW Rota1.
  3. Shinkailepas limpets at NW Rota.
  4. A large Alvinocaris shrimp.
  5. A slope covered with sulfur crusts.
  6. Sulfur deposits outcrop on a ridge at NW Rota.

Video Links:

  1. Two species of shrimp found here at NW Rota-1 volcano.
  2. Some of the dead marine life observed on the sea floor at NW Rota-1.
  3. Dive at NW Rota.
  4. Underwater volcanic eruption at Brimstone vent on NW Rota-1 was the first eruption ever witnessed.
  5. Despite the active eruptive activity nearby, two species of shrimp thrive on NW Rota-1.


  1. Chadwick, W. W., Cashman, K. V., Embley, R. W., Matsumoto, H., Dziak, R. P., de Ronde, C. E. J., Lau, T. K., Deardorff, N. D., Merle, S. G., 2008. Direct video and hydrophone observations of submarine explosive eruptions at NW Rota-1 volcano, Mariana arc. Journal of Geophysical Research 113 (B8), 1-23.
  2. Dziak, R. P., Baker, E. T., Shaw, A. M., Bohnenstiehl, D. R.,Chadwick, Jr. W. W., Haxel, J. H., Matsumoto, H., Walker, S. L., 2012. Flux measurements of explosive degassing using a yearlong hydroacoustic record at an erupting submarine volcano. Geochem. Geophys. Geosyst. 13, Q0AF07, doi:10.1029/2012GC004211.
  3. Embley, R. W., Chadwick, W. W., Jr., Baker, E. T., Butterfield, D. A., Resing, J. A., de Ronde, C. E., Tunnicliffe, V., Lupton, J. E., Juniper, S. K., Rubin, K. H., Stern, R. J., Lebon, G. T., Nakamura, K., Merle, S. G., Hein, J. R., Wiens, D. A., Tamura, Y., 2006. Long-term eruptive activity at a submarine arc volcano. Nature 441 (7092), 494-497.
  4. Huber, J. A., Cantin, H. V., Huse, S. M., Welch, D. B., Sogin, M. L., Butterfield, D. A., 2010. Isolated communities of Epsilonproteobacteria in hydrothermal vent fluids of the Mariana Arc seamounts: FEMS Microbiol Ecol. 73 (3), 538-549.
  5. Lupton, J., Lilley, M., Butterfield, D., Evans, L., Embley, R., Massoth, G., Christenson, B., Nakamura, K., Schmidt, M., 2008. Venting of a separate CO2-rich gas phase from submarine arc volcanoes: Examples from the Mariana and Tonga-Kermadec arcs. Journal of Geophysical Research 113 (B8), 1-21.
  6. 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.
  7. Resing, J. A., Lebon, G., Baker, E. T., Lupton, J. E., Embley, R. W., Massoth, G. J., Chadwick, W. W. Jr., Ronde, C. E. J., 2007. Venting of acid-sulfate fluids in a high-sulfidation setting at NW Rota-1 submarine volcano on the Mariana Arc. Econ. Geol. 102, 1047-1061.
  8. Stern, R. J., Tamura, Y., Embley, R. W., Ishizuka, O., Merle, S. G., Basu, N. K., Kawabata, H., Bloomer, S. H., 2008. Evolution of West Rota Volcano, an extinct submarine volcano in the southern Mariana Arc. Evidence from sea floor morphology, remotely operated vehicle observations and 40Ar-39Ar geochronological studies. Island Arc 17 (1), 70-89.
  9. Stevens, C. J., Limen, H., Pond, D. W., Gelinas, Y., Juniper, S. K., 2008. Ontogenetic shifts in the trophic ecology of two alvinocaridid shrimp species at hydrothermal vents on the Mariana Arc, western Pacific Ocean. Marine Ecology Progress Series 356, 225–237.

Website References:

  1. Submarine Ring of Fire 2004 (accessed 12/24/2015)
  2. Submarine Ring of Fire 2006 (accessed 12/24/2015)
  3. Submarine Ring of Fire 2014 (accessed 12/24/2015)
  4. Woods Hole Oceanographic Institution: ROV JASON/MEDEA: Operations Summary (accessed 12/24/2015)

Cruise Reports:

  1. Submarine Ring of Fire 2006 (accessed 12/24/2015)
  2. Submarine Ring of Fire 2004 (accessed 12/24/2015)
  3. NT05-17 cruise report (accessed 02/27/2017)
  4. NT10-13 leg2 cruise report (accessed 02/27/2017)