Vent Sites:
Hakurei ore deposit (= Hakurei site)
Host Rock:
dacitic to andesitic caldera with lava dome
Notes on Vent Field Description:
located in SE caldera floor; Tanahashi et al. (2006): "first discovery of Kuroko-type ore deposit in the Izu-Bonin back-arc rift"; note: spreading rate from primary literature not from Bird (2003); Neptune Minerals Plc, 21 Feb. 2007, applications by Neptune Minerals Japan Kabushiki Kaisha: "Neptune's applications cover 6 highly prospective areas, including the Hakurei hydrothermal field, discovered by Japanese researchers in 2003 approximately 500km south-southeast of Tokyo. Subsequent research has delineated a complex of sulphide mounds and chimneys covering an area of 700m x 500m, at a water depth of around 900m."; Honsho et al. (2013): AUV Urashima dives in 2011, "autonomous underwater vehicle (AUV) surveys of a large-scale hydrothermal deposit called the Hakurei site located in the Bayonnaise knoll caldera of the Izu-Ogasawara island arc"
Notes Relevant to Biology:
Year and How Discovered (if active, visual confirmation is listed first):
2003 temperature anomalies, but camera survey observed inactive vent deposits
Discovery References (text):
[Iizasa, K et al (2004) A first extensive hydrothermal field associated with Kuroko-type deposit in a Silicic Submarine caldera in a Nascent Rift Zone, Izu-Ogasawara (Bonin) arc, Japan. OCEANS'04 MTTS/IEEE: 991-996]
[Tomizawa, N et al (2004) Exploration for a hydrothermal sulfide deposit in a submarine caldera, Izu-Ogasawara arc. OCEANS'04 MTTS/IEEE: 997-1003]
[Tanahashi, M et al (2006) A large hydrothermal sulfide deposit discovered in the Bayonnaise knoll, Izu-Bonin back-arc rift. Shigen Chishitsu 56: 185-196 (Japanese)]
Watanabe, H., pers. comm., 2009: "Dr. K. Iizasa in AIST conducted a cruise of R/V Natsushima and ROV HyperDolphin"
Other References (text):
Tanahashi, M. et al. (2008) Myojin Rift, Izu–Bonin Arc as the Modern Analog of Hokuroku Basin, Northeast Japan: Geotectonic Significance of the New Hydrothermal Deposit in the Back-Arc Rift. Resource Geology 58: 301–312.
Honsho, C., et al. (2013) Mapping the Bayonnaise knoll caldera and the Hakurei hydrothermal deposit with autonomous underwater vehicle using side-scan and multi-beam sonars. 2013 IEEE InternationalUnderwater Technology Symposium, doi:10.1109/UT.2013.6519848.