Urashima Vent
Latitude: 12.917οN Longitude: 143.650οE Depth: 2922 mbsl
Urashima site is located north of Pika site in the southern Mariana arc/trough region. In 2010 several gray smokers venting hydrothermal fluids (280°C) were observed (Nakamura et al. 2013). The site includes black dead chimneys, red-brown shimmering chimneys, and areas of yellow microbial mat exposed to low-temperature hydrothermal fluids (Toki et al., 2015). In addition to microbial mats there are anemones, crabs and shrimp were also found in the area (YK10-10 cruise report).
Table 1: Operations history for Urashima vent
| Ship/ Platform | Operation | Year | Dive Number | References |
| RR1413 R/V Roger Revelle/ Jason | XBT, CTD
EM122 multibeam logging |
2014 | J2-797, J2-801 | Submarine Ring of Fire 2014-Ironman |
| YK10-10 Yokosuka/ Shinkai 6500 | Not found | 2010 August | 1214- 1219 | YK10-10 cruise report |
| YK10-11 Yokosuka/ Shinkai 6500 | Not found | 2010 September | 1220, 1227, 1228 |
Beauliue et al., 2011 |
Table 2: Vent activity and host rocks
| Activity and host rocks | References | |
| Vent Activity | Active | Submarine Ring of Fire 2014-Ironman |
| Host Rocks | Not found | |
Table 3: Vent fluid characteristics
| Vent Fluids | References | |
| Temperature (°C) | 321, 280 to 70 | YK10-10 cruise report |
| pH | 2.85 | Toki et al., 2015 |
| Composition | Active gray smoker, and clear fluid chimneys with iron mat including one big ~10m | YK10-10 cruise report |
| CO2 (mM) | 23.2 | Toki et al., 2015 |
| Mn (mM) | 2.22 | Toki et al., 2015 |
| Fe (mM) | 6.37 | Toki et al., 2015 |
| (3He/4He) | 8.09 | Toki et al., 2015 |
| CH4 (mM) | 0.0108 | Toki et al., 2015 |
| Cl- (mM) | 623 | Mino et al., 2013 |
| Na (mM) | 456 | Mino et al., 2013 |
| K (mM) | 37 | Mino et al., 2013 |
| Ca (mM) | 31 | Mino et al., 2013 |
| NH4+ (μM) | <100 | Mino et al., 2013 |
| SO42- (mM) | -4.11 | Mino et al., 2013 |
| H2S (mM) | 2.4 | Mino et al., 2013 |
| Alkalinity (meq/kg) | -1.42 | Nakamura et al., 2013 |
| General name | Phylum | References |
| Bacterial iron mats | YK10-10 cruise report | |
| Anemone | Arthropoda | YK10-10 cruise report |
| Crabs | Arthropoda | YK10-10 cruise report |
| Shrimp | Arthropoda | YK10-10 cruise report |
Images:
- Sulfide chimneys coated with iron-based microbial mat at the Urashima vent site (note: search “sulfide chimneys”).
Video Links:
- Footage from the dives at Snail Vent and Urashima (note: search “Footage from the dives at Snail Vent and Urashima”).
- Goldern Horn Chimney at Urashima Vent (note: search “Goldern Horn Chimney at Urashima Vent”).
References:
- Mino, S., Makita, H., Toki, T., Miyazaki, J., Kato, S., Watanabe, H., … & Sawabe, T. (2013). Biogeography of Persephonella in deep-sea hydrothermal vents of the Western Pacific.
- Nakamura, K., Toki, T., Mochizuki, N., Asada, M., Ishibashi, J. I., Nogi, Y., … & Okino, K. (2013). Discovery of a new hydrothermal vent based on an underwater, high-resolution geophysical survey. Deep Sea Research Part I: Oceanographic Research Papers, 74, 1-10.
- 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.
Website References:
- Submarine Ring of Fire 2014 http://oceanexplorer.noaa.gov/explorations/14fire/logs/december20/december20.html (accessed 11/26/2015)
Cruise Reports:
- Submarine Ring of Fire 2014-Ironman cruise report http://www.pmel.noaa.gov/eoi/marianas/SRoF-Ironman-2014-CruiseReport-withdivelogs.pdf (2/26/2017)
- Yokosuka Cruise Report YK10-10 http://www.godac.jamstec.go.jp/catalog/data/doc_catalog/media/YK10-10_all.pdf (accessed 11/26/2015)
- Yokosuka Cruise Report YK10-11 http://www.godac.jamstec.go.jp/catalog/data/doc_catalog/media/YK10-11_all.pdf (accessed 11/26/2015)