Hostname: page-component-78c5997874-dh8gc Total loading time: 0 Render date: 2024-11-10T15:05:32.988Z Has data issue: false hasContentIssue false
  • English
  • Français

A km-scale illite alteration zone in sedimentary wall rocks adjacent to a hydrothermal fluorite vein deposit

Published online by Cambridge University Press:  09 July 2018

O. Brockamp  and
N. Clauer
O. Brockamp*
Affiliation:
Fachbereich Geowissenschaften, Universität Bremen, Postfach 330 440, D-28334 Bremen, Germany
N. Clauer
Affiliation:
Centre de Géochimie de la Surface (CNRS-ULP), 1, rue Blessig, F-67084 Strasbourg, France
*
*E-mail: michelse@min.uni-bremen.de
Get access Rights & Permissions [Opens in a new window]

Abstract

In a study of wall-rock alteration in the 1.4 km long Würmtal adit at the Käfersteige hydrothermal vein deposit (northern Black Forest, Germany) illite was found to be the only clay mineral within the Bunter sandstone and intercalated claystone. Illite occurs mainly as a detrital mineral in the claystone, whereas it is hydrothermally neoformed in the sandstone, either in the pores or as an alteration product of K-feldspar. The extensive occurrence of authigenic illite along the entire 1.4 km long profile confirms that the fluids migrated far into the sandstone.

The authigenic illite formed during a first pulse of high-temperature fluids (Th of ~220°C) with a low salinity (~1 wt.% NaCleq). These fluids also dissolved Sr and Rb from detrital illite of the claystones at the vein. A later hydrothermal pulse with a lower temperature (~70–150°C) and higher salinity (21–28 wt.% NaCleq) silicified the sandstone adjacent to the vein and caused partial substitution of OH- by F- in the structure of the detrital and neoformed illite along the profile.

Within analytical error, the K-Ar dates for the neoformed illite of the <2 µm fraction are the same along the profile (~150 Ma). During this hydrothermal process, the age of the detrital illite within the claystone was reset from 310 to 190 Ma. The illite-rich <0.2 µm fractions yield ages of ~142 Ma (sandstone) indicating a Jurassic origin. The uniform age data for illite in the sandstone and in the claystone are probably due to extensive migration of hot fluids through the wall rocks.

The hydrothermal fluids are attributed to recycled meteoric water and brines that ascended from the basement into the cover rocks during the opening of the North Atlantic and/or the nearby Tethys area.

Keywords

alterationK-Ar datingillitefluid inclusionsBlack ForestGermany
Type
Research Article
Information
Clay Minerals , Volume 40 , Issue 2 , June 2005 , pp. 245 - 260
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2005

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

Behr, H.J. (1989) Die geologischen Aktivitäten von Krustenfluiden. Niedersächsische Akademie der Geowissenschaften, 1, 7–42.Google Scholar
Behr, H.J. & Horn, E.E. (1984) Unterscheidungskriterien fur Mineralisationen des varistischen und postvaristischen Zyklus, die aus der Analyse fluider Einschlüsse gewinnbar sind. Schriftenreihe der Gesellschaft Deutscher Metallhütten- und Bergleute, 41, 255–269.Google Scholar
Bodnar, R.J. (1993) Revised equation and table for determining the freezing point depression of H2ONaCl solutions. Geochimica et Cosmochimica Ada, 57, 683–684.CrossRefGoogle Scholar
Bonhomme, M.G., Buhmann, D. & Besnus, Y. (1983) Reliability of K-Ar dating of clays and silifications associated with vein mineralizations in Western Europe. Geologische Rundschau, 72, 105–117.Google Scholar
Brockamp, O., Zuther, M. & Clauer, N. (1987) Epigenetic-hydrothermal origin of the sedimenthosted Mullenbach uranium deposit, Baden-Baden, W-Germany. Pp. 87-98 in: Uranium Mineralization. New Aspects on Geology, Mineralogy, Geochemistry and Exploration Methods. Proceedings of the Uranium Symposium DMG-, GDMB-, SGA-Meeting, Aachen 198. (G. Friedrich et al., editors). Monograph Series of Mineral Deposits, 27. E. Schweizerbart'sche Verlagsbuchhandlung, Germany.Google Scholar
Brockamp, O., Clauer, N. & Zuther, M. (2003) Authigenic sericite record of a fossil geothermal system: the Offenburg trough, Central Black Forest, Germany. International Journal of Earth Sciences, 92, 843–851.Google Scholar
Brown, G. & Brindley, G.W. (1980) X-ray diffraction procedures for clay mineral identification. Pp. 305-359 in: Crystal Structures of Clay Minerals and their X-ray Identificatio. (G.W. Brindley & G. Brown, editors). Monograph 5, Mineralogical Society, London.Google Scholar
Cathelineau, M. & Izquierdo, G. (1988) Temperature composition relationships of authigenic micaceous minerals in the Los Azufres geothermal system. Contributions to Mineralogy and Petrology, 100, 418–428.Google Scholar
Cathelineau, M., Fourcade, S., Clauer, N., Buschaert, S., Rousset, D., Boiron, M.C., Meunier, A., Lavastre, V. & Javoy, M. (2004) Dating multistage paleofluid percolations: A K-Ar and 818O study of fracture illite from altered Hercynian plutonites at the basement/cover interface (Oitou High, France). Geochimica et Cosmochimica Acta, 68, 2529–2542.Google Scholar
Clauer, N. & Chaudhuri, S. (1995) Clays in Crustal Environments. Isotope Dating and Tracing. Springer, Berlin, 359 pp.CrossRefGoogle Scholar
Clauer, N., O'Neil, J.R. & Furlau, S. (1995) Clay minerals as a record of temperature conditions and duration of thermal anomalies in the Paris basin. Clay Minerals, 30, 1–13.CrossRefGoogle Scholar
Clauer, N., Zwingmann, H. & Chaudhuri, S. (1996) Isotope (K-Ar and oxygen) contraints on the extent and importance of the Liassic hydrothermal activity in western Europe. Clay Minerals, 31, 301–318.CrossRefGoogle Scholar
Drits, V., Środoń J. & Eberl, D.D. (1997) XRD measurements of mean crystallite thickness of illite and illite/smectite: reappraisal of the Kubler index and the Scherrer equation. Clays and Clay Minerals, 45, 461-475.Google Scholar
Flehmig, W. & Gehlken, P.L. (1988) Chemical variations in the octahedral composition of Paleozoic illites and their genetic significance: an infrared spectroscopic study. Neues Jahrbuch für Mineralogie, Monatshefie, 249-258.Google Scholar
Flehmig, W. & Kurze, R. (1973) Die quantitative infrarotspektroskopische Phasenanalyse von Mineralgemengen. Neues Jahrbuch fiir Mineralogie, Abhandlungen, 119, 101 – 112.Google Scholar
Franzke, H.J., Ahrendt, H., Kurz, S. & Wemmer, K. (1996) K-Ar Datierungen von Illiten aus Kataklasiten der Floβbergstörung im südöstlichen Thüringer Wald und ihre geologische Interpretation. Zeitschrift fur geologische Wissenschaften, 24, 441–456.Google Scholar
Gehlen, K. von (1987) Formation of Pb-Zn-F-Ba mineralizations in SW-Germany: a status report. Fortschritte der Mineralogie, 65, 87–113.Google Scholar
Geyer, O.F. & Gwinner, M.P. (1991) Geologie von Baden-Wiirttemberg. Schweizerbart, Stuttgart, Germany, 482 pp.Google Scholar
Hagedorn, B. & Lippolt, H.J. (1994) Isotopische Alter von Zerruttungszonen als Altersschranken der Freiamt-Sexau-Mineralisation (Mittlerer Schwarzwald). Abhandlungen des geologischen Landesamtes Baden-Württemberg, 14, 205–219.Google Scholar
Heier, K.S. (1970) Rubidium. Pp. 37-D-l in: Handbook of Geochemistry, Section II-. (K.H. Wedepohl et al, editors). Springer, Heidelberg, Germany.Google Scholar
Heydemann, A. (1969) Tables. Pp. 376-412 in: Handbook of Geochemistry, Section . (K.H. Wedepohl et al., editors). Springer, Heidelberg, Germany.Google Scholar
Hunziker, J.C., Frey, M., Clauer, N., Dallmeyer, R.D., Friedrichsen, H., Flehmig, W., Hochstrasser, K., Roggwiler, P. & Schwander, H. (1986) The evolution of illite to muscovite: mineralogical and isotopic data from the Glarus Alps, Switzerland. Contributions to Mineralogy and Petrology, 92, 157–180.CrossRefGoogle Scholar
Koritnig, S. (1977) Fluorine. Pp. 9 - K - l in: Handbook of Geochemistry, Section II-. (K.H. Wedepohl et al., editors). Springer, Heidelberg, Germany.Google Scholar
McDowell, S.D. & Elders, W.A. (1980) Authigenic layer silicate minerals in borehole Elmore 1, Salton Sea Geothermal Field, California, U.S.A. Contributions to Mineralogy and Petrology, 74, 923–310.Google Scholar
Mertz, D.F. (1987) Isotopengeochemische und mineralogische Untersuchungen an postvaristischen hydrothermalen Silikaten. Dr. rer nat. Thesis, Universität Heidelberg, Germany.Google Scholar
Metz, R. (1971) Mineralogisch-landeskundliche Wanderungen im Nordschwarzwald. Sonderheft zur Zeitschrift: Der Aufschluβ, 20. VMFG, Heidelberg, Germany, 516 pp.Google Scholar
Meyer, M., Brockamp, O., Clauer, N., Renk, A. & Zuther, M. (2000) Further evidence for a Jurassic mineralizing event in central Europe: K-Ar dating of hydrothermal alteration and fluid inclusion systematics in wall rocks of the Kafersteige fluorite vein deposit in the northern Black Forest, Germany. Mineralium Deposita, 35, 754–761.Google Scholar
Mitchell, J.G. & Halliday, A.N. (1976) Extent of Triassic- Jurassic hydrothermal ore deposits on the North Atlantic margins. Transactions of the Institute of Mining and Metallurgy, B, 85, 159–161.Google Scholar
Möller, P., Maus, H. & Gundlach, H. (1982) Die Entwicklung von FluBspatmineralisationen im Bereich des Schwarzwaldes. Jahreshefte des geologischen Landesamtes Baden-Württemberg, 24, 35–70.Google Scholar
Möller, P. (1986) Anorganische Geochemie. Springer, Aachen, 326 pp.Google Scholar
Möller, P., Lüders, V. & Franzke, H.J. (1990) Gangtektonik und SEE-Fraktionierung in Fluoriten des Schwarzwaldes. Pp. 297-307 in: DFG-Schwerpunktprogramm Intraformationale Lagerstättenbildun. (G. Friedrich, editor). Kolloquiumsband, Berlin, Germany.Google Scholar
Ncube, A.N., Horn, E.E. & Amstutz, G.C. (1979) The fluorite deposit Käfersteige in the Buntsandstein near Pforzheim, Black Forest. Neues Jahrbuch fur Mineralogie, Monatshefte, 49–61.Google Scholar
Perry, E. & Hower, J. (1970) Burial diagenesis in Gulf coast pelitic sediments. Clays and Clay Minerals, 18, 165–177.Google Scholar
Potter, R.W. (1977) Pressure corrections for fluid inclusion homogenization temperatures based on the volumetric properties of the system NaCl-H2O. US Geological Survey Journal of Research, 5, 603–607.Google Scholar
Potts, P.J. (1992) A Handbook of Silicate Rock Analysis. Blackie & Son, Glasgow, UK, 622 pp.CrossRefGoogle Scholar
Steiger, R.H. & Jager, E. (1977) Subcommission on geochronology: convention on the use of decay constants in geo- and cosmochronology. Earth and Planetary Science Letters, 36, 359–362.Google Scholar
Stueber, A.M. (1978) Strontium. Pp. 38-D-l in: Handbook of Geochemistry, Section II-. (K.H. Wedepohl et al., editors). Springer, Heidelberg, Germany.Google Scholar
Wagner, T. & Jochum, J. (2002) Fluid-rock interaction processes related to hydrothermal vein-type mineralization in the Siegerland district, Germany: implications from inorganic and organic alteration patterns. Applied Geochemistry, 17, 225–243.Google Scholar
Warr, L.N. (1998) Tonmineralkristallinität und Kristallgröβe als Indikatoren für die Bedingungen der Diagenese und der niedrigtemperierten Metamorphose in tonführenden Gesteinen. Habilitations-Schrift, Geologisch-Pälaontologisches Institut, Universitat Heidelberg, Germany, 231 pp.Google Scholar
Warr, L.N. & Rice, A.H.N. (1994) Interlaboratory standardization and calibration of clay mineral crystallinity and crystallite size data. Journal of Metamorphic Geology, 12, 141 – 152.Google Scholar
Wood, B.J. & Walther, J.V. (1986) Fluid flow during metamorphism and its implications for fluid-rock ratios. Pp. 89–108 in: Fluid Rock Interactions during Metamorphis. (J.V. Walther & B.J. Wood, editors). Advances in Physical Geochemistry, 5. Springer, Berlin.Google Scholar
Yau, Y.C., Peacor, D.R., Beane, R.E., Essene, E.J. & McDowell, S.D. (1988) Microstructures, formation mechanism, and the depth-zoning of phyllosilicates in geothermally altered shales, Salton Sea, California. Clays and Clay Minerals, 36, 1 – 10.Google Scholar
Zhang, Y. & Franz, J.D. (1987) Determination of the homogenization temperatures and the densities of supercritical fluids in the system NaCl-KCl-CaCl2- H2O using synthetic fluid inclusions. Chemical Geology, 64, 335–350.Google Scholar
Zuther, M. & Brockamp, O. (1988) The fossil geothermal system of the Baden-Baden trough (Northern Black Forest, Germany). Chemical Geology, 71, 337–353.Google Scholar