Southern Explorer

Fortin, D. Ferris, F.G. Scott, S.D. (1998) Formation of Fe-silicates and Fe-oxides on bacterial surfaces in samples collected near hydro-thermal vents on the Southern Explorer Ridge in the northeast Pacific Ocean. Am. Min. 83 1399-1408... 

Layer-silicates Recent studies have also demonstrated the potential microbial influence on clay mineral (layer silicates) formation at hydrothermal vents. Bacterial cells covered (or completely replaced) with a Fe-rich silicate mineral (putative nontronite), in some cases oriented in extracellular polymers (as revealed by TEM analysis), were found in deep-sea sediments of Iheya Basin, Okinawa Trough (Ueshima Tazaki, 2001), and in soft sediments, and on mineral surfaces in low-temperature (2-50°C) waters near vents at Southern Explorer Ridge in the northeast Pacific (Fortin etal., 1998 Fig. 8.6). The Fe-silicate is believed to form as a result of the binding and concentration of soluble Si and Fe species to reactive sites (e.g. carboxyl, phosphoryl) on EPS (Ueshima Tazaki, 2001). Formation of Fe-silicate may also involve complex binding mechanisms, whereas metal ions such as Fe possibly bridge reactive sites within cell walls to silicate anions to initiate silicate nucleation (Fortin etal., 1998). Alt (1988) also reported the presence of nontronite associated with Mn- and Fe-oxide-rich deposits from seamounts on the EPR. The presence of bacteria-like filaments within one nontronite sample was taken to indicate that bacterial activity may have been associated with nontronite formation. Although the formation of clay minerals at deep-sea hydrothermal vents has not received much attention, it seems probable that based on these studies, biomineralisation of clay minerals is ubiquitous in these environments. 

Fig. 8.6 Transmission electron microscope photomicrograph of Fe-rich layer silicate surrounding microbial remains, which appear as holes in this unstained section. Sample from Southern Explorer Ridge. The mineral has a composition similar to nontronite. From D. Fortin etal., Amer. Mineral., 83, 1399—1408. Reproduced with permission. Copyright Mineralogical Society of America (1998).

Leveille, R.J., Williams-Jones, A., Cousens, B.L., Gillis, K., Channing, C., Chadwick, W.W. Jr., Embley, R.W., Butterfield, D.A. and Juniper, K. (2002) The Nature of Sulfide Weathering in the Submarine Environment Evidence From the Southern Explorer Ridge, American Geophysical Union, Fall Meeting, Abstract T11C-1269. 

Fig. 2.44. logaoi-pH range.s for Kuroko ore fluid.s and midoceanic ridge hydrothermal. solution. I Kuroko 2 Axial Explorer 3 2I°N, Southern Juan de Fuca 4 2I°N, Endeavour 5 Guaymas. Temperature = 250°C, ESr (total reduced sulfur concentration) = 6.6 x 10 m. HM hematite, MT magnetite, PY pyrite, PO pyrrhotite. Dotted line Au solubility (ppm) (Shikazono, 1988). 

Caritat, P. de, Lech, M.E., Jaireth, S., Pyke, J., Fisher, A. 2007. Riverina Region Geochemical Survey, Southern New South Wales and Northern Victoria. Cooperative Research Centre for Landscape Environments and Mineral Exploration Open File Report, 234, 843p. + CD-ROM. 

Smuk, K.A., WiLLiAMS ONES, A.E., Francis, D. 1997. The Carmacks hydrothermal event an alteration study in the southern in the southern Dawson Range, In Yukon Geology 1996, Exploration and Geological Services Division, Yukon Region, Indian and northern Affairs, Canada, 92-106. 

Historical exploration has highlighted the Fischell s Brook salt/potash prospect as a possible analog to the Sussex deposits in southern New Brunswick. The prospect is located approximately 15 kilometres south of the Town of St. George adjacent to and underlying the Trans-Canada Highway. The deposit is associated with a gravity anomaly that is approximately 10.5 x 8.5... 

The Jesuit explorers of Lake Superior compared it to a bow and arrow, the Canadian shore being the bow, the southern or United States shore tire bowstring, and the Keweenaw promontory the arrow. In this... 

Bufotenine was isolated from skin and parotid gland of the toad Bufo vulgaris in 1893, and from plants and mushrooms. It is also foimd in the toad Bufo marinus that lives in the southern part of the United States and the Caribbean, and in Bufo alvarius, found in the southwestern United States. Amazon explorers had described poisoning by toad and mushroom preparations more than 400 years ago. Street names include black stone, Chan Su, Chinese love stones, cohoba, rock hard. Stud 100, and toad. 

The uneven distribution of elements across the face of the earth has shaped history - stimulating trade and encouraging exploration and cultural exchange, but also promoting exploitation, war, and imperialism. Southern Africa has paid dearly for its gold and the elemental carbon of its diamonds. Many rare but technologically important elements, such as tantalum and uranium, continue to be mined from poor regions of the world under conditions (and for reasons) that some consider pernicious and hazardous. 

Ashley, P.M., Craw, D., Graham, B.P. and Chappell, D.A. (2003) Environmental mobility of antimony around mesothermal stibnite deposits, New South Wales, Australia and southern New Zealand. Journal of Geochemical Exploration, 77(1), 1-14. 

Baroni, F., Boscagli, A., Di Leila, L.A. et al. (2004) Arsenic in soil and vegetation of contaminated areas in southern Tuscany (Italy). Journal of Geochemical Exploration, 81(1-3), 1-14. 

Huisman, D.J., Vermeulen, F.J.H., Baker, J. et al. (1997) A geological interpretation of heavy metal concentrations in soils and sediments in the southern Netherlands. Journal of Geochemical Exploration, 59, 163-74. 

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