South Chamorro Vent



Latitude: 13.788οN                  Longitude: 146.003οE             Depth: 3083 m bsl

South Chamorro Seamount is a serpentinite mud volcano on the Mariana forearc (Fryer et al., 2006). Pore fluids from the South Chamorro Seamounts suggest a slab source, as evidenced by their lower chlorinity and higher K and Rb (Mottl, 1992). The fluids are also enriched in dissolved carbonate, light hydrocarbons, ammonia and borate (Mottl et al., 2003; Holm et al., 2009). The summit of South Chamorro Seamount has small carbonate chimney structures (Fryer et al. 1999). The biodiversity includes archaea, bacteria and some eukaryotes such as calyptogena clams, galatheid crabs, gastropods, mussels and tube worms (Mottl et al., 2003; Curtis et al., 2013; Takai et al., 2005; Yamanaka et al., 2015; Fryer et al., 1997; Fujioka et al., 2002).

Table 1: Operations history for S. Chamorro vent

Ship/ Platform Operation Year Dive Number References
NT 12-04 R/V Natsushima/ Hyper-dolphin Not found 2012 HPD#1349 to HPD#1351

NT12-04 cruise report

YK03-07 Yokosuka/ Shinkai 6500 Not found 2003 August-September 0777-0780

YK03-07 cruise report

Table 2: Activity and rock types

Activity and host rocks References
Activity Active mud volcanism

Fryer et al., 1999

IODP-MCME 366 Proposal

Rocks types Muds are mainly Serpentinite and small fragments of metabasic rocks

Fryer et al., 1999

Fryer et al., 2006

Table 3: Vent fluid characteristics

Property Bottom seawater Vent Fluids References
Distance from the trench (km) 85 km IODP-MCME 366 Proposal
Temperature (οC) 1.67  3  Mottl et al., 2003; McIntyre et al., 2013
pH 8 12.5 IODP-MCME 366 Proposal
Composition Interstitial fluids of pH 12.6 associated with serpentinized mud at the South Chamorro seamount are enriched in dissolved carbonate, light hydrocarbons, ammonia and borate. Mottl et al., 2003

Holm et al., 2009

Alkalinity (meq/kg) 2.3 62 IODP-MCME 366 Proposal
Clorinity (mmol/kg) 542 510 IODP-MCME 366 Proposal
CH4 (mmol/kg) 4×10-7




Mottl et al., 2003

McIntyre et al., 2013

CO2  mmol/kg 26 McIntyre et al., 2013
Sulfate  (mmol/kg) 28 28 IODP-MCME 366 Proposal
Mg (mmol/kg) 52.4 <0.01 IODP-MCME 366 Proposal
Ca (mmol/kg) 10.2 0.3 IODP-MCME 366 Proposal
Na (mmol/kg) 466 610 IODP-MCME 366 Proposal
Na/Cl (molar) 0.86 1.2 IODP-MCME 366 Proposal
K (mmol/kg) 10.1 19 IODP-MCME 366 Proposal
Li (μmol/kg) 26 0.4 IODP-MCME 366 Proposal
Rb (μmol/kg) 1.37 10 IODP-MCME 366 Proposal
Cs (μmol/kg) 0.0022 0.3 IODP-MCME 366 Proposal
Sr (μmol/kg) 90 10 IODP-MCME 366 Proposal
Ba (μmol/kg) 0.14 0.4 IODP-MCME 366 Proposal
B (μmol/kg) 410 3200 IODP-MCME 366 Proposal
Si (μmol/kg) 190 70 IODP-MCME 366 Proposal
F (μmol/kg) 67 47 IODP-MCME 366 Proposal
Mn (μmol/kg) 0 0.01 IODP-MCME 366 Proposal
Fe (μmol/kg) 0 2 IODP-MCME 366 Proposal

*IODP-MCME 366- International Ocean Discovery Program-Mariana Convergent Margin Expedition 366.

Table 4: Vent Biology

General name Phylum Class/Order Family Genus/Species References
Archaea Crenarchaeota Mottl et al., 2003

Curtis et al., 2013

Archaea Euryarchaeota Mottl et al., 2003

Curtis et al., 2013

Alkaliphilic bacteria Proteobacteria Alteromonadales Alteromonadaceae Marinobacter alkaliphilus sp. Takai et al., 2005
Calyptogena clams Mollusca Veneroida Vesicomyidae Yamanaka et al., 2015
Galatheid crabs Arthropoda Fryer et al., 1997
Gastropods Mollusca Fryer et al., 1997
Mussels Mollusca Mytiloida Mytilidae Bathymodiolus sp. Fryer et al., 1997; Fujioka et al., 2002; Fujioka et al., 2001; Yamanaka et al., 2015
Tube worms Annelida Fryer et al., 1997



Video links:

  1. J-EDI JAMSTEC E-Library for Deep-sea Images (note: search “South Chamorro”).


  1. Curtis, A. C., Wheat, C. G., Fryer, P., Moyer, C. L., 2013. Mariana Forearc Serpentinite Mud Volcanoes Harbor Novel Communities of Extremophilic Archaea. Geomicrobiology Journal 30 (5), 430-441.
  2. Fryer, P., Gharib, J., Ross, K., Savov, I., Mottl, M. J., 2006. Variability in serpentinite mudflow mechanisms and sources: ODP drilling results on Mariana forearc seamounts. Geochemistry Geophysics Geosystems 7 (8), Q08014, doi:10.1029/2005GC001201.
  3. Fryer, P., Mottl, M. J., 1997. “Shinkai 6500” Investigations of a resurgent mud volcano on the Southeastern Mariana forearc. JAMSTEC J. Deep Sea Res. 13, 103-114.
  4. Fryer, P., Wheat, C. G., Mottl, M. J., 1999. Mariana blueschist mud volcanism Implications for conditions within the subduction zone. Geology 27 (2), 103–106.
  5. Fujioka, K., Yamanaka, T., Gamo, T., Inagaki, F., Miwa, T., Sato, H., 2001. An introduction to the Serpentinite Biosphere in the Mariana Forearc: Capsule of the Deep Subsurface Biosphere from the Chamorrow Seamount. Bull. Earthq. Res. Inst. Univ. Tokyo 76, 417-424.
  6. Fujioka, K., Yamanaka, T., Gamo, T., Inagaki, F., Miwa, T., Sato, H., Okamoto, T., Oda, H., 2002. Serpentines as a capsule of the deep subsurface biosphere: Evidence from the Chamorro Seamount, Mariana forearc. JAMSTEC J. Deep Sea Res. 20, 9-16.
  7. Holm, N. G., Neubeck, A., 2009. Reduction of nitrogen compounds in oceanic basement and its implications for HCN formation and abiotic organic synthesis. Geochemical Transactions10 (9), 1-11.
  8. McIntyre, C. P., McNichol, A. P., Roberts, M. L., Seewald, J. S., von Reden, K. F., Jenkins, W. J., 2013. Improved Precision of Radiocarbon Measurements for CH4 and CO2 Using GC and Continuous-Flow AMS achieved by Summation of Repeated Injections. Radiocarbon 55 (2–3), 677–685.
  9. Mottl, M. J., 1992. Pore Waters from Serpentinite Seamounts in the Mariana and Izu-Bonin Forearcs, Leg 125: Evidence for Volatiles from the Subducting Slab. Proceedings of the Ocean Drilling Program, Scientific Results 125, 373-385.
  10. Mottl, M. J., Komor, S. C., Fryer, P., Moyer, C. L., 2003. Deep-slab fluids fuel extremophilic Archaea on a Mariana forearc serpentinite mud volcano: Ocean Drilling Program Leg 195. Geochemistry, Geophysics, Geosystems 4 (11) 9009, doi: 10.1029/2003GC000588.
  11. Takai, K., Moyer, C. L., Miyazaki, M., Nogi, Y., Hirayama, H., Nealson, K. H., Horikoshi, K., 2005. Marinobacter alkaliphilus sp. nov., a novel alkaliphilic bacterium isolated from subseafloor alkaline serpentine mud from Ocean Drilling Program Site 1200 at South Chamorro Seamount, Mariana Forearc. Extremophiles 9, 17–27.
  12. Yamanaka, T., Shimamura, S., Nagashio, H., Yamagami, S., Onishi, Y., Hyodo, A., Mampuku, M., Mizota, C., 2015. A Compilation of the Stable Isotopic Compositions of Carbon, Nitrogen, and Sulfur in Soft Body Parts of Animals Collected from Deep-Sea Hydrothermal Vent and Methane Seep Fields: Variations in Energy Source and Importance of Subsurface Microbial Processes in the Sediment-Hosted Systems. In: Ishibashi, J., Okino, K., Sunamura, M. (Eds.), Subseafloor Biosphere Linked to Hydrothermal Systems: TAIGA Concept. Springer Japan, 105-129.

Website References:

  1. J-DESC Japan Drilling Earth Science Consortium: IODP Mariana Convergent Margin Expedition 366: (accessed 09/12/2015)
  2. JAMSTEC (Japan Agency for Marine Earth Science and Technology) E-library of Deep-sea Images (JEDI) (accessed 11/24/2015)
  3. Marine geology and geochemistry division of, department of oceanography, university of Hawaii, Manoa: (accessed 09/12/2015)

Cruise Reports:

  1. Natsushima cruise report NT12-04 (accessed 2/27/2017)
  2. Yokosuka cruise report YK03-07 (accessed 2/27/2017)