Latitude: 12.9187οN Longitude: 143.6487οE Depth: 2774 m bsl
The Pika site is located on the top of an off-axial seamount (Ishibashi et al., 2006), and was identified as localities created by long-term hydrothermal activity (Yoshikawa et al., 2012). The seamount is composed of pillow lavas with minor sediment covers while there are several discrete vents with active and inactive sulfide chimneys (Kakegawa et al., 2008). The highest observed temperature of the black smoker was 330 °C (Yoshikawa et al., 2012) while the fluids are rich with Cl, Fe (Ishibashi et al., 2006) and H2S (Kato et al., 2010) and has a low pH (Ishibashi et al., 2006). The biodiversity around the Pika site include several bacterial species as well as barnacles, shrimp and snails (Kato et al., 2010; Kato et al., 2012; Kumagai et al., 2015).
Table 1: Operations history for Pika vent
| Ship/ Platform | Operation | Year | Dive Number | References |
| Hakurei-Maru #2 cruise | BMS (Benthic Multi-coring System) | 2004 January | Not found | YK05-09-Leg2 |
| Yokosuka Cruise 05-09 | Shinkai 6500 | 2005 July-August | 906 | YK05-09-Leg2 |
| Yokosuka Cruise 10-11 | Shinkai 6500 | 2010 September | 1222, 1225, 1226 | YK10-11 cruise report |
| Yokosuka Cruise 10-10 | Shinkai6500 | 2010 August | 1214 | YK10-10 cruise report |
Table 2: Vent activity and host rocks
| Activity and host rocks | References | |
| Activity | Active | Kato et al., 2010 |
| Host Rocks | Tholeiitic andesite | Kakegawa et al., 2008 |
Table 3: Vent fluid characteristics
| Vent Fluids | References | |
| Temperature (οC) | 315 οC -330 οC | Baker et al., 2005; Ishibashi et al., 2006 |
| pH | 3 at 25 οC2.86 | Ishibashi et al., 2006Toki et al., 2015 |
| Composition | Metal rich, high Cl concentration and low pH | Ishibashi et al., 2004Kakegawa et al., 2008 |
| CO2 (mM) | 33.7-69.1 | Toki et al., 2015 |
| H2 (μM) | 301 | Toki et al., 2015 |
| Mn (mM) | 1.13 | Toki et al., 2015 |
| Fe (mM) | 7.38 | Toki et al., 2015 |
| He (μM) | 1.83 | Toki et al., 2015 |
| CH4 (μM) | 7.2-29.9μ | Toki et al., 2015 |
Table 4: Vent Biology
| General name | Phylum | Class/Order | Family | Genus/Species | References |
| Bacteria | Aquificae | Aquificales | Hydrogenothermaceae | Persephonella | Kato et al., 2012 |
| Bacteria | Proteobacteria | Gammaproteobacteria | Thiomicrospira | Kato et al., 2010; Kato et al., 2012 | |
| Bacteria | Proteobacteria | Epsilonproteobacteria | Campylobacterales | Hydrogenimonas | Kato et al., 2010; Kato et al., 2012 |
| Bacteria | Proteobacteria | Epsilonproteobacteria | Campylobacterales | Sulfurimonas | Kato et al., 2010; Kato et al., 2012 |
| Bacteroidetes | Kato et al., 2010 | ||||
| Bacteria | Proteobacteria | Zetaproteobacteria | Mariprofundus | Kato et al., 2012 | |
| Barnacles | Arthropoda | Multicrustacea | Neoverrucidae | Neoverruca brachylepadoformis | Kumagai et al., 2015 |
| Shrimp | Arthropoda | Malacostraca | Alvinocarididae | Chorocaris vandoverae | Kumagai et al., 2015 |
| Snail | Mollusca | Gastropoda | Provannidae | Alviniconcha hessleri | Kumagai et al., 2015 |
Images:
- J-EDI JAMSTEC E-Library for Deep-sea: http://www.godac.jamstec.go.jp/jedi/public/Sec102.jsf note: search “Pika”.
Video Links:
- J-EDI JAMSTEC E-Library for Deep-sea: http://www.godac.jamstec.go.jp/jedi/public/Sec102.jsf note: search “Pika”.
References:
- Baker, E. T., Massoth, G. J., Nakamura, K., Embley, R. W., de Ronde, C. E. J., and Arculus, R. J., 2005. Hydrothermal activity on near-arc sections of back-arc ridges: Results from the Mariana Trough and Lau Basin. Geochemistry, Geophysics, Geosystems 6 (9), doi: 10.1029/2005GC000948.
- Ishibashi, J., Suzuki, R., Yamanaka, T., Toki, T., Kimura, H., Noguchi, T., Urabe, T., 2006. Seafloor hydrothermal activity at offaxial seamounts of backarc spreading in southern Mariana Trough. Geochimica et Cosmochimica Acta 70 (18), A279-A279.
- Ishibashi, J., Yamanaka, T., Kimura, H., Hirota, A., Toki, T., Tsunogai, U., Gamo, T., Utsumi, M., Roe, K., Miyabe, S., Okamura, K. 2004. Geochemistry of Hydrothermal Fluids in South Mariana Backarc Spreading Center. American Geophysical Union, Fall Meeting 2004, abstract #V44A-05.
- Kato, S., Takano, Y., Kakegawa, T., Oba, H., Inoue, K., Kobayashi, C., Utsumi, M., Marumo, K., Kobayashi, K., Ito, Y., Ishibashi, J., Yamagishi, A., 2010. Biogeography and biodiversity in sulfide structures of active and inactive vents at deep-sea hydrothermal fields of the Southern Mariana Trough. Applied Environmental Microbiology 76 (9), 2968-2979.
- Kato, S., Nakamura, K., Toki, T., Ishibashi, J., Tsunogai, U., Hirota, A., Ohkuma, M., Yamagishi, A., 2012. Iron-based microbial ecosystem on and below the seafloor: a case study of hydrothermal fields of the Southern Mariana Trough. Frontiers in Microbiology 3, doi: 10.3389/fmicb.2012.00089. 13.
- Kumagai, H., Watanabe, H., Yahagi, T., Kojima, S., Nakai, S., Toyoda, S., Ishibashi, J., 2015. Evaluating Hydrothermal System Evolution Using Geochronological Dating and Biological Diversity Analyses. In: Ishibashi, J., Okino, K., Sunamura, M. (Eds.), Subseafloor Biosphere Linked to Hydrothermal Systems: TAIGA Concept. Springer Japan, 49-59.
- Toki, T., Ishibashi, J., Noguchi, T., Tawata, M., Tsunogai, U., Yamanaka, T., and Nakamura, K., 2015, Chemical and Isotopic Compositions of Hydrothermal Fluids at Snail, Archaean, Pika, and Urashima Sites in the Southern Mariana Trough. In: Ishibashi, J., Okino, K., Sunamura, M. (Eds.), Subseafloor Biosphere Linked to Hydrothermal Systems: TAIGA Concept. Springer Japan, 587-602.
- Yoshikawa, S., Okino, K., and Asada, M., 2012. Geomorphological variations at hydrothermal sites in the southern Mariana Trough: Relationship between hydrothermal activity and topographic characteristics. Marine Geology 303-306, 172-182.
- Kakegawa, T., Utsumi, M., and Marumo, K., 2008, Geochemistry of Sulfide Chimneys and Basement Pillow Lavas at the Southern Mariana Trough (12.55°N-12.58°N): Resource Geology 58 (3), 249-266.
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 11/26/2015)
Cruise Reports:
- Yokosuka cruise report YK05-09-Leg2 http://www.godac.jamstec.go.jp/catalog/data/doc_catalog/media/YK05-09_leg2_all.pdf
- Yokosuka cruise report YK10-11 http://www.godac.jamstec.go.jp/catalog/data/doc_catalog/media/YK10-11_all.pdf
- Yokosuka cruise report YK10-10 http://www.godac.jamstec.go.jp/catalog/data/doc_catalog/media/YK10-10_all.pdf