Atlantis 11 deep

Singer, A. StofFers, P. (1987) Mineralogy of a hydrothermal sequence in a core from the Atlantis 11 Deep, Red Sea. Clay Min. 22 251-267... 

Mat. Sci. Materials in Electronics 3 201-205 Taitel-Goldman, N. Singer, A. (2001) High-re-solution transmission electron microscopy study of newly formed sediments in the Atlantis 11 Deep, Red Sea. Clays Clay Min. 

Blanc G, Anschutz P (1995) New stratification in the hydrothermal brine system of the Atlantis 11 Deep, Red Sea. Geology 23(6) 543-546... 

Atlantis Deep deposit, 17 690 Atmosphere. See also Air entries circulation of water with, 26 7-12 natural photocatalytic reactions in, 19 100... 

Fig. 15.8 Well ciystalline euhedral platy hematite (a), poorly crystalline spherical Si-containing hematite together with ring-like layer Fe-silicates ( ) (b), and akaganeite (c) from the Atlantis Deep, Red Sea, (Photo H.-Ch. Bartscherer) (Schwertmann etal., unpubl.)...

Schwertmarm, U. Friedl, J. Stanjek, H., Murad E. Bender-Koch,Ch. (1998) Iron oxides and smectites in sediments of the Atlantis Deep II, Red Sea. Eur. J. Mineral. 10 953-967... 

Akaganeite is formed in natiue under the same conditions used in laboratory synthesis, i. e. in the presence of chloride and at elevated temperatures (e. g. 60 °C). Examples are the hot brines of the Atlantis Deep of the Red Sea and the hot springs of similar composition of the White Island volcano. New Zealand. Natural and synthetic akaganeites frequently display similar crystal morphologies. 

Ramboz, C., Orphanidis, E., Oudin, E., Thisse, Y., and Rouer, O. (2008), Metastable fluid diseharge by the Atlantis Deep submarine geyser the heat-mass balance of the stratified lower brine revisited in the light of new fluid inelusion data. This volume. 

We turn our attention now to the hydrothermal brines of the Red Sea. An oceanic survey in 1963 discovered pools of hot, saline, and metal-rich brines along the axial rift of the Red Sea (Degens and Ross, 1969 Hoffmann, 1991). The dense brines pond in the rift s depressions, or deeps. The Atlantis II deep contains the largest pool, which measures 5 x 14 km and holds about 5 km3 of supersaline brine. The deep holds two layers of brine. The lower brine contains about 25 wt.% dissolved salts and exists at temperatures up to 60 °C. Table 6.8 shows the brine s average composition. A somewhat cooler, less saline water overlies the lower brine, separating it from normal seawater. 

Table 6.8. Chemical composition of the lower brine, Atlantis II deep, Red Sea...

From the perspective of ore genesis, these results seem disappointing in light of the fluid s high degree of supersaturation. Shanks and Bischoff (1977), for example, estimate that about 60 mg of sphalerite alone precipitate from each kg of ore fluid feeding the Atlantis II deep. The reaction to form chalcocite,... 

Cole,T.G. (1983) Oxygen isotope geothermometry and origin of smectites in the Atlantis II Deep, Red Sea. Earth Planetary Sci. Letters 66 166-176... 

Atlantis II Deep (Red Sea) and the uptake of amino acids by synthetic P-FeOOH Cln. Geochim. Cosmochim. Acta 47 1465-1470 Holm,T.R., Anderson, M.A., Iverson, D.G. Stanforth, R.S. (1979) Heterogeneous interaction of arsenic in aquatic systems. ACS Symposium Ser. Chemical modelling of aqueous systems Speciation, sorption, solubility, kinetics. 711-736... 

A. (2002) Lepidocrocite in hydrothermal sediments of the Atlantis II and Thetis Deeps,... 

Ramboz, C., and Danis, M. (1990). Superheating in the Red Sea The heat-mass balance of the Atlantis II Deep revisited. Earth Planet. Sci. Lett. 97, 190-210... 

Figure 30. Schematic cross-section of the Atlantis II Deep. From Zierenberg and Shanks (1983) used with permission of the Economic Geology Publishing Company.

Zierenberg RA, Shanks WC III (1983) Mineralogy and geochemistry of epigenetic features in metalliferous sediment, Atlantis II Deep, Red Sea. Econ Geol 78 57-72... 

Figure 13. Correlation of He/" He with reciprocal of " He concentration (l/" He) from two brine basins in the Red Sea after Winckler et al. (2001a). Samples from the Atlantis brine define a mixing between RSDW (Red Sea Deep Water) and a MORB-derived component ( He/ He = 1.27x10 = 9.2 Ra), samples from Kebrit brine lie on a mixing line between RSDW and a " He-emiched crustal end-member ( He/ He = 1x10 ). The different hehum isotopic fingerprints of the two brines reflect the geological setting, i.e., the northward progression of seafloor spreading in the Red Sea.

Hartmarm M, Scholten JC, Staffers P, Wehner F (1998) Hydrographic stracture of brine-filled deeps in the Red Sea new results from the Shaban, Kebrit, Atlantis 11 and Discovery Deep. Mar Geol 144 311-330 Higgins S. (2001) Extraterrestrial tracer in the sea evaluation and application of He in interplanetary dirst particles as a constant flux tracer in marine sediments. PhD dissertation, Columbia University, New York, New York... 

B) lethyoliths reeovered from deep marine sediments from the Paeifie and Atlantie oeeans. Data from Girard and Albarede (1996) and Elderfield and Pagett (1986). 

If the hot vent lies in a depression such as the Atlantis II Deep in the Red Sea, the results of the hydrothermal reactions are very evident (see Figure 1). Water is removed together with magnesium and sulfate, and calcium is released from the basalt. Rock salt (NaCl), anhydrite (CaS04), and silica (SiOa) are formed and the brine becomes saturated with these solids. Sulfide metals are coprecipitated with iron sulfide (FeS). 

Figure 1 Depth profiles of chlorinity (Cl, g kg" ), calcium, magnesium and sulfate (mol kg ) in the Red Sea Atlantis II deep on 22-23 March 1976.

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