Hostname: page-component-cd9895bd7-dk4vv Total loading time: 0 Render date: 2024-12-23T16:01:16.979Z Has data issue: false hasContentIssue false

Mineralogy of a hydrothermal sequence in a core from the Atlantis II Deep, Red Sea

Published online by Cambridge University Press:  09 July 2018

A. Singer
Affiliation:
The Seagram Center for Soil and Water Sciences, The Faculty of Agriculture, The Hebrew University of Jerusalem, Rehovot, Israel
P. Stoffers
Affiliation:
Geologisch-Paläontologisches Institut und Museum der Universität Kiel, Olshausenstrasse 40/60, Kiel 2300, W. Germany

Abstract

The clay fractions from a 1191-cm long sediment core in the SW Basin of the Atlantis II Deep, Red Sea, were investigated by XRD, electron microscopy and chemical analysis. Talc dominates in the botton portion of the core, near the brine discharge vent. At 1183 cm depth, the clay consists of vermiculite/chlorite and chrysotile. These minerals are of hydrothermal origin and two possible formation pathways are proposed: (i) vermiculite/chlorite and chrysotile formed by the submarine alteration of previously deposited talc; (ii) vermiculite/chlorite and chrysotile authigenically precipitated as a result of changes in the chemical composition of the brine. At 1170 cm depth, a new depositional sequence results from the progressive alteration of swelling 2:1 minerals into vermiculite. At 1025 cm, Mg-rich clay minerals such as chlorite, chrysotile and talc again become prominent. The upper part of the core is characterized by a transition from non-expanding Mg-rich clay minerals to Fe-rich expanding clays, principally nontronite. Periodically, the content of well-crystallized oxides such as hematite in the layers increases. At 1025 cm, some of the Fe-oxides have a morphology similar to that of akaganéite. In the uppermost part of the core, iron oxides appear to consist of a poorly crystalline hydrothermal hematite. An attempt has been made to correlate the various mineralogical assemblages geochemically.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1987

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Bäker, H. & Richter, H. (1973) Die rezente hydrothermal-sedimentätte Lagerstätte Atlantis II-Tief im Roten Meer. Geol. Rundseh. 62, 697741.CrossRefGoogle Scholar
Bischoff, J.L. (1969) Red Sea geothermal brine deposits: their mineralogy, chemistry and genesis. Pp. 368401 in: Hot Brines and Recent Heavy Metal Deposits in the Red Sea (Degens, E. T. & Ross, D. A., editors). Springer Verlag, Berlin.Google Scholar
Bischoef, J.L. (1972) A ferroan nontronite from the Red Sea geothermal system. Clays Clay Miner. 20, 217223.Google Scholar
Brockamp, O., Goulart, E., Harder, H. & Heydemann, A. (1978) Amorphous copper and zinc sulfides in the metalliferous sediments of the Red Sea. Contr. Mineral. Petrol. 68, 8588.Google Scholar
Cole, T.G. (1983) Oxygen isotope geothermometry and origin of smectite in the Atlantis II Deep, Red Sea. Earth Planet. Sci. Lett. 66, 166176.Google Scholar
Cole, T.G. & Shaw, H.F. (1983a) The nature and origin of authigenic smectites in some recent marine sediments. Clay Miner. 18, 239252.CrossRefGoogle Scholar
Cole, T.G. & Shaw, H.F. (1983b) Kerolite associated with anhydrite in sediments from the Atlantis II Deep, Red Sea. Clay Miner. 18, 325331.Google Scholar
Eberl, D.D., Jones, B.F. & Khoury, H.N. (1982) Mixed-layer kerolite/stevensite from the Amargosa Desert, Nevada. Clays Clay Miner. 30, 321326.CrossRefGoogle Scholar
Goulart, E.P. (1976) Different smectite types in sediments of the Red Sea. Geol. Jb. D17, 135149.Google Scholar
Harder, H. (1976) Nontronite synthesis at low temperatures. Chem. Geol. 18, 169180.CrossRefGoogle Scholar
Harder, H. (1978) Synthesis of iron layer silicate minerals under natural conditions. Clays Clay Miner. 26, 6572.Google Scholar
Hayman, R.M. & Kastner, M. (1981) Hot spring deposits on the East Pacific Rise at 21°N preliminary description of mineralogy and genesis. Earth Planet. Sci. Lett. 53, 363381.Google Scholar
Holm, N.G., Dowler, M.J., Wadsten, T. & Arrhenius, G. (1983) β-FeOOH.Cln (akaganéite) and Fe1-xO (wüstite) in hot brine from the Atlantis II Deep (Red Sea) and the uptake of amino acids by synthetic β-FeOOH Cln . Geoehim. Cosmochim. Acta 47, 14651470.Google Scholar
Lonsdale, P.F., Bischoff, J.L., Burns, V.M., Kastner, M. & Sweeney, R.E. (1980) A high temperature hydrothermal deposit on the sea bed at a Gulf of California spreading center. Earth Planet. Sci. Lett. 49, 820.Google Scholar
Mackenzie, R.C., Follett, E.A.C. & Meldau, R. (1971) The oxides of iron, aluminium, and manganese. Pp. 315344 in: The Electron-Optical Investigation of Clays (Gard, J. A., editor). Mineralogical Society, London.Google Scholar
Mehra, O.P. & Jackson, M.L. (1960) Iron oxide removal from soils and clays by dithionite-citrate system buffered with sodium bicarbonate. Clays Clay Miner. 7, 319327.Google Scholar
Mifsud, A., Fornes, V. & Raussell-Colom, J.A. (1977) Natural alteration of vermiculite to chrysotile. Am. Miner. 62, 12251231.Google Scholar
Moody, J.B. (1976) Serpentinization: a review. Lithos 9, 125138.Google Scholar
Murdmaa, I.P. & Rozanova, T.V. (1976) Hess Deep bottom sediments. Pp. 252260 (in Russian) in: Geological-Geophysical Researches in the Southeastern Part of the Pacific Ocean. Nauka, Moscow.Google Scholar
Oberlin, A. (1979) Electron microscopy and diffraction. Pp. 217242, in: Data Handbook for Clay Materials and other Non-Metallic Minerals (van Olphen, H. & Fripiat, J. J., editors). Pergamon Press, London.Google Scholar
Schmitz, W., Singer, A., Bäcker, H. & Stoffers, P. (1982) Hydrothermal serpentine in a Hess Deep sediment core. Marine Geol. 46, M17M25.Google Scholar
Schneider, W. & Schumann, D. (1979) Tonminerale in Normalsedimenten, hydrothermal beeinflussten Sedimenten und Erzschlämmen des Roten Meeres. Geol. Rundsch. 68, 631648.CrossRefGoogle Scholar
Schumann, D. (1978) Mineralogische Untersuchungen an Sedimennten aus dem Atlantis H Tief, Rotes Meer. Dr rer. nat. Diss. Univ. Mainz, 689 pp. (unpubl.).Google Scholar
Seyfried, W.E. & Dibble, W.E. (1978) Chemical exchange and secondary mineral formation during seawater-periodotite interaction: an experimental study. Geol. Soc. Am. Abst. with Programs 10, 490.Google Scholar
Shanks, W.C. & Bischoff, J.L. (1977) Ore transport and deposition in the Red Sea geothermal system: a geochemical model. Geochim. Cosmochim. Acta 41, 15071519.Google Scholar
Singer, A. & Stoffers, P. (1981) Hydrothermal vermiculite from the Atlantis II Deep, Red Sea. Clays Clay Miner. 29, 654658.Google Scholar
Singer, A., Stoffers, P., Heller-Kallai, L. & Szefranek, D. (1984) Nontronite in a deep sea core from the South Pacific. Clays Clay Miner. 32, 375383.CrossRefGoogle Scholar
Sudo, T., Shimoda, S., Yotsumoto, H. & Aita, S. (1981) Electron Micrographs of Clay Minerals. Elsevier, Amsterdam.Google Scholar
Upite, A., Konstant, Z.A. & Vaivoblis, A. (1963) Synthesis of magnesium hydrosilicates from Mg hydroxide rehydrated at 400° and silicic acid. Latv. PSR Zinat Acad Vosis, Kim. Ser. 6, 625-635; cited in Bonatti, E., Honnorez, J. & Gartner, S. (1973) Sedimentary serpentinites from the Mid-Atlantic Ridge. J. Sed. Petrol. 43, 728735.Google Scholar
Weiss, H.M. (1979) Rasterelektronenmikroscopische Untersuchungen an Erzschlämmenn des Roten Meeres, Atlantis II Tiefers. M.Sc. Thesis, Heidelberg University (unpubl.).Google Scholar
Weiss, H.M., Nöltner, T. & Stoffers, P. (1980) Das Auftreten von Ilvait in den Erzschlämmen des Toten Meeres. N. Jb. Miner. Abh. 139, 239253.Google Scholar
Whitney, G. & Eberl, D.D. (1982) Mineral paragenesis in a talc-water experimental hydrothermal system. Am. Miner. 67, 944949.Google Scholar