SE Pacman Vent
Latitude: 19.178oN Longitude: 147.061oE Depth: 3536 m bsl
Vent Sites: Baseball Mitt, Cerulean Springs (Fryer et al., 1999)
SE Pacman is a trench-proximal serpentinite mud volcano located in the Mariana forearc. The active seeps along the SE flank of Pacman Seamount, the Cerulean Springs, produce thin brucite chimneys (Fryer et al., 1999). The Cerulean Springs are where the steepest gradients in chlorinity were measured; brucite chimneys had not previously been reported from fluid seeps on the sea floor (Fryer et al., 1999). Lower chlorinity and higher K and Rb of pore fluids from Pacman seamount indicates a slab source (Fryer et al., 1999). Similar to the other forearc mud volcanos, archaea dominate the SE Pacman ecosystem (Curtis et al., 2013).
Table 1: Operations history for SE Pacman vent
| Ship/ Platform | Operation | Year | Dive Number | References |
| Not found | SeaMARK II bathymetry data | Not found | Fryer et al., 1996; Fryer et al., 1992 | |
| Not found | Seasat A Satellite Scatterometer (SASS) data | Not found | Fryer et al., 1996; Fryer et al., 1992 | |
| TN-154 Thompson ROV Jason-2 | ROV JASON 2 | 2003 April | J2-027 to J2-029, J2-041 | Woods Hole Oceanographic Institution: ROV JASON/MEDEA: Operations Summary (note: click “Files- operations summary”) |
| YK03-07 Yokosuka/ Shinkai 6500 | Not found | 2003 September | 784 | YK03-07 cruise report |
Table 2: Activity and Rock types
| Activity and Rock types | References | |
| Activity | Active venting | Fryer et al., 1999 |
| Rock types | blue to bluish-green serpentine muds | Fryer et al., 1999 |
Table 3: Vent fluid characteristics
| Bottom seawater | Vent Fluids | References | |
| Distance from the trench | 60 km | Hulme et al., 2010 | |
| Maximum flow (cm/yr) | 13.6 | Hulme et al., 2010 | |
| pH | 8 | 10.8 | Hulme et al., 2010 |
| Composition | Ca-rich,low-alkalinity, and low magnesium fluids in mud volcanoes near the trench. | Wheat et al., 2008 | |
| Alkalinity (meq/kg) | 2.3 | 3 | IODP-MCME 366 |
| Clorinity (mmol/kg) | 542 | 302 | IODP-MCME 366 |
| Sulfate (mmol/kg) | 28 | 8.6 | IODP-MCME 366 |
| Mg (mmol/kg) | 52.4 | 0.1 | IODP-MCME 366 |
| Ca (mmol/kg) | 10.2 | 48.8 | IODP-MCME 366 |
| Na (mmol/kg) | 466 | 222 | IODP-MCME 366 |
| Na/Cl (molar) | 0.86 | 0.735 | IODP-MCME 366 |
| K (mmol/kg) | 10.1 | 2 | IODP-MCME 366 |
| Li (μmol/kg) | 26 | 1.3 | IODP-MCME 366 |
| Rb (μmol/kg) | 1.37 | 1.2 | IODP-MCME 366 |
| Cs (μmol/kg) | 0.0022 | 0.0113 | IODP-MCME 366 |
| Sr (μmol/kg) | 90 | 313 | IODP-MCME 366 |
| Ba (μmol/kg) | 0.14 | 0.63 | IODP-MCME 366 |
| B (μmol/kg) | 410 | 87 | IODP-MCME 366 |
| Si (μmol/kg) | 190 | 68 | IODP-MCME 366 |
| F (μmol/kg) | 67 | 0 | IODP-MCME 366 |
| Mn (μmol/kg) | 0 | 0.06 | IODP-MCME 366 |
| Fe (μmol/kg) | 0 | 0.18 | IODP-MCME 366 |
Table 4: Vent Biology
| General name | Phylum | References |
| Archaea | Crenarchaeota | Curtis et al., 2013 |
| Archaea | Euryarchaeota | Curtis et al., 2013 |
Images:
- J-EDI JAMSTEC E-Library of Deep-sea Images, note search “SE Pacman”.
Video Links:
- SHINKAI 6500 0784, J-EDI JAMSTEC E-Library of Deep-sea Images, note search “SE Pacman”.
References:
- 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.
- 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.
- Fryer, P. (1996). Evolution of the Mariana convergent plate margin system. Reviews of Geophysics, 34(1), 89-125.
- Hulme, S. M., Wheat, C. G., Fryer, P., Mottl, M. J., 2010. Pore water chemistry of the Mariana serpentinite mud volcanoes: A window to the seismogenic zone. Geochemistry geophysics geosysems 11(1), Q01X09, doi: 10.1029/2009GC002674.
- Wheat, C., Fryer, P., Fisher, A., Hulme, S., Jannasch, H., Mottl, M., Becker, K., 2008. Borehole observations of fluid flow from South Chamorro Seamount, an active serpentinite mud volcano in the Mariana forearc. Earth and Planetary Science Letters 267 (3-4), 401-409.
Website References:
- JAMSTEC (Japan Agency for Marine Earth Science and Technology) E-library of Deep-sea Images (JEDI) http://www.godac.jamstec.go.jp/jedi/public/Sec102.jsf (accessed 11/15/2015)
- Woods Hole Oceanographic Institution: ROV JASON/MEDEA: Operations Summary http://www.whoi.edu/main/jason/operations-summary (accessed 11/15/2015)
Cruise Reports:
- IODP Mariana Convergent Margin Expedition 366, unpublished IODP proposal http://iodp.tamu.edu/scienceops/precruise/mariana/505-Full5.pdf (accessed 11/15/2015)
- Yokosuka cruise report YK03-07 http://www.godac.jamstec.go.jp/catalog/data/doc_catalog/media/YK03-07_all.pdf (accessed 2/27/2017)