BABB, MORB, low-K andesite, rhyolithe
PMS, polymetallic massive sulfides
Notes on Vent Field Description:
central Valu Fa Ridge; Vai Lili means "very hot" in Tongan; temperatures in 1989 were on the order of 300 C, claimed as first discovery of black smokers in western Pacific back-arc basins; large, active sulfide deposits, barite-silica chimneys, low-temperature Fe-oxides, and associated Fe-Mn crusts in the axial rift (100 m x 400 m approx. dimensions), fault controlled discharge, black and white smokers, low pH; 4 km south of Mariner; note: 2003 plume survey indicated diminished activity; "the volcanic domes that dominate Vai Lili extend for hundreds of meters to the north and south"; "Hydrothermal activity at Vai Lili in 2005 consisted of 121°C fluid pooled beneath marcasite-lined flanges [Tivey et al., 2005; M. K. Tivey, manuscript in preparation, 2008], and 70°C clear fluid emanating from a small Fe-oxide chimney. No higher temperature venting was observed in 2005, but many large sulfide mounds and relic flanges were identified along the small volcanic ridges"; 2012 cruise report: ROV Quest 4000 Dive Q322; located within Nautilus Minerals tenement
Notes Relevant to Biology:
small fauna population around white smokers only, small shrimps, large gastropods, white crabs (Desbruyeres, D. et al. 1994)
Year and How Discovered (if active, visual confirmation is listed first):
Discovery References (text):
JL Charlou et al. (1990) Hydrothermal activity in the Lau back arc basin: Plumes and hot fluids chemistry. AAPG Bulletin (American Association of Petroleum Geologists) 74: 6
Fouquet et al., Nature, 349, 778-781, 1991, Hydrothermal activity and metallogenesis in the Lau back-arc basin
Fouquet, Y., et al. (1991) Hydrothermal activity in the Lau back-arc basin: sulfides and water chemistry. Geology 19: 303-306.
Other References (text):
[(deposits sampled just south of this position) Von Stackelberg et al., Bundesanstalt Geowissenschaften Rohstoffe Circular 2, 3-14, 1985]
Fouquet, Y., et al., 1993. Metallogenesis in Back-Arc Environments: The Lau Basin example. Econ. Geol. 88, pp. 2154–2181
Desbruyeres, D. et al. (1994) Deep-sea hydrothermal communities in Southwestern Pacific back-arc basins (the North Fiji and Lau Basins): Composition, microdistribution and food web. Marine Geology 116: 227-242
Baker, E.T. et al. (2005) Hydrothermal activity on near-arc sections of back-arc ridges: results from the Mariana Trough and Lau Basin. Geochem. Geophys. Geosyst. 6: Q09001, doi:10.1029/2005GC000948
Ferrini, V. et al. (2008) Variable morphologic expression of volcanic, tectonic, and hydrothermal processes at six hydrothermal vent fields in the Lau back-arc basin. GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS, VOL. 9, Q07022, doi:10.1029/2008GC002047.
2012 cruise report, accessed 6 May 2015: http://oceanexplorer.noaa.gov/explorations/12fire/logs/summary/srof12-cruisereport-final.pdf.