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Late-orogenic alpine-type (apatite)-quartz fissure vein mineralization in the Rheinisches Schiefergebirge, NW Germany: mineralogy, formation conditions and lateral-secretionary origin

Published online by Cambridge University Press:  05 July 2018

T. Wagner  and
N. J. Cook
T. Wagner*
Affiliation:
Mineralogisches Institut der Universität Würzburg Am Hubland, D-97074 Würzburg, Germany
N. J. Cook
Affiliation:
Geological Survey of Norway, N-7491 Trondheim, Norway
*
* E-mail: thomas.wagner@mail.uni-wuerzburg.de
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Abstract

Mineralogical, geochemical and fluid inclusion investigations of a representative suite of fissure vein mineralizations in the Rheinisches Schiefergebirge, NW Germany indicate a link to the latest stage of the Variscan orogenic evolution. Model P-T-conditions during initiation of fibrous fissure vein quartz growth are in the range 370–420°C at 0.2–0.7 kbar. The dataset suggests significant fluid cooling during evolution of the vein systems. Minimum temperatures at the end of fibrous quartz growth lie in the range 140–190°C, with conductive heat transfer and heat consumption during interaction with wallrock believed to be the main mechanisms responsible. Wallrock alteration is characterized by leaching and mobilization of most of the dominant vein components (quartz, albite, apatite), notably Si, Na and P. The principal stage of vein formation is, on the basis of available data, believed to relate to a process of intra-formational redistribution or lateral secretion. However, part of those elements deposited both in wallrock and fissure veins were probably supplied directly by the external fluid. Rates of fissure opening and material deposition were in equilibrium during the principal growth stage of fibrous quartz. However, this situation evolved due to a slowing down of material supply and deposition coupled with an increased rate of fissure opening to produce open fissures and formation of idiomorphic quartz crystals within them. Deposition depths were in the range of 0.6–2.1 km, appreciably lower than estimations of overburden. We believe therefore that formation of the fissure vein systems took place along the retrograde late–orogenic exhumation path, in a transitional stage between Variscan collision and a late- to post-orogenic extensional regime. Fluid composition characteristics also strongly suggest a relationship to the latest stages of the Variscan mineralization cycle in which low–salinity brines dominate. Development of fissure vein systems during the latest stages of continental collision, identified here from the Variscan orogeny, can be considered analogous with similar phenomena in the Alpine orogenic belt.

Keywords

Alpine-type fissure veinsRheinisches Schiefergebirgelateral secretion
Type
Research Article
Information
Mineralogical Magazine , Volume 64 , Issue 3 , June 2000 , pp. 539 - 560
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2000

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References

Ahrendt, H., Clauer, N., Hunziker, J.C. and Weber, K. (1983) Migration of folding and metamorphism in the Rheinisches Schiefergebirge deduced from K-Ar and Rb-Sr age determinations. Pp. 323–39 in: Intracontinental Fold Belts (Martin, H. and Eder, F.W., editors). Springer, Berlin-Heidelberg.CrossRefGoogle Scholar
Arthaud, F. and Matte, P. (1977) Late Paleozoic strike-slip faulting in southern Europe and northern Africa: Result of a right-lateral shear zone between the Appalachians and the Urals. Geol. Soc. Amer. Bull., 88, 1305–20.2.0.CO;2>CrossRefGoogle Scholar
Bauer, G., Ebert, A., Hesemann, J., von Kamp, H., Müller, D., Pietzner, H., Podufahl, P., Scherp, A. and Wellmer, F.W. (1979) Die Blei-Zink-Erzlagerstätten von Ramsbeck und Umgebung. Geol. Jb., D33, 1–377.Google Scholar
Behr, H.J., Horn, E.E., Frentzel-Beyme, K. and Reutel, C. (1987) Fluid inclusion characteristics of the Variscan and post-Variscan mineralizing fluids in the Federal Republic of Germany. Chem. Geol., 61, 273–85.CrossRefGoogle Scholar
Bornhardt, W. (1912) Über die Gangverhältnisse des Siegerlandes und seiner Umgebung, Teil II. Archiv für Lagerstättenforschung, 8, 444 pp.Google Scholar
Brown, P.E. (1989) FLINCOR: A microcomputer program for the reduction and investigation of fluid inclusion data. Amer. Mineral., 74, 1390–3.Google Scholar
Cathelineau, M. (1988) Cation site occupancy in chlorites and illites as a function of temperature. Clay Miner., 23, 471–85.CrossRefGoogle Scholar
Cathelineau, M. and Nieva, D. (1985) A chlorite solid solution geothermometer. The Los Azufres (Mexico) geothermal system. Contrib. Mineral. Petrol., 91, 235–44.CrossRefGoogle Scholar
de Caritat, P., Hutcheon, I. and Walshe, J.L. (1993) Chlorite geothermometry: A review. Clay Miner., 41, 219–39.CrossRefGoogle Scholar
Dittmar, U., Meyer, W., Oncken, O., Schievenbusch, T., Walter, R. and von Winterfeld, C. (1994) Strain partioning across a fold and thrust belt: the Rhenish Massif, Mid-European Variscides. J. Struct. Geol., 16, 1335–52.CrossRefGoogle Scholar
Franke, W. and Oncken, O. (1990) Geodynamic evolution of the North-Central Variscides – a comic strip. Pp. 187–94 in: The European Geotraverse: Integrative Studies (Freeman, R., Giese, P. and Mueller, S., editors). European Science Foundation, Strasbourg.Google Scholar
Franke, W., Eder, W., Engel, W. and Langenstrassen, F. (1978) Main aspects of geosynclinal sedimentation in the Rhenohercynian zone. Z. Dt. Geol. Ges., 129, 201–16.Google Scholar
Grant, J.A. (1986) The isocon diagram – a simple solution to Gresen's equation for metasomatic alteration. Econ. Geol., 81, 1976–82.CrossRefGoogle Scholar
Hein, U.F. (1993) Synmetamorphic Variscan siderite mineralization of the Rhenish Massif, Central Europe. Mineral. Mag., 57, 451–67.CrossRefGoogle Scholar
Hein, U.F. and Behr, H.J. (1994) Zur Entwicklung von Fluid systemen im Verlauf der Deformationsgeschicht e des Rhenoherzynikums. Göttinger Arbeiten zur Geoloie und Paläontologiel., Sonderband 1, 191–3.Google Scholar
Hein, U.F. and Kirnbauer, T. (1996) Hydrothermaler Apatit in spätvariskischen Mineralgängen des südlichen Rheinischen Schiefergebirges: Verbreitung, Mineralogie und Geochemie. Eur. J. Mineral., 8, Beiheft 1, 141.Google Scholar
Henk, A. (1995) Late Variscan exhumation histories of the southern Rhenohercynian zone and western Mid-German Crystalline Rise: results from thermal modelling. Geol. Rundsch., 84, 578–90.CrossRefGoogle Scholar
Henk, A. (1997) Gravitational orogenic collapse vs plate-boundary stresses: a numerical modelling approach to the Permo-Carboniferous evolution of Central Europe. Geol. Rundsch., 86, 39–55.CrossRefGoogle Scholar
Hoefs, J. and Stalder, H.A. (1977) Die C-Isotop enzusammensetzung von CO2-haltigen Flüssigkeitseinsc hlüssen in Kluftquar zen der Zentralalpen. Schweiz. Mineral. Petrogr. Mitt., 57, 329–47.Google Scholar
Holland, T., Baker, J. and Powell, R. (1998) Mixing properties and activity-composition relationships in the system MgO-FeO-Al2O3-SiO2-H2O. Eur. J. Mineral., 10, 395–406.CrossRefGoogle Scholar
Jowett, E.C. (1991) Fitting iron and magnesium into the hydrothermal chlorite geothermometer. Program with abstracts, Geol. Assoc. Can. - Mineral. Assoc. Can. Joint Annual Meeting, 16, A62.Google Scholar
Kirnbauer, T. (1998) Alpinotype Zerrklüfte. Jahrbücher des Nassaui schen Vereins für Naturkunde, Sonderband 1, 150–6.Google Scholar
Langhoff, C. (1997) Mineralchemische und mikrother mometrische Untersuchungen an den Gangminerali sationen der Pb-Zn-Lagerstätte Ramsbeck im Sauerland. Unpubl. Thesis, Univ. Hamburg.Google Scholar
Mercolli, I., Schenker, F. and Stalder, H.A. (1984) Geochemie der Veränderungen von Granit durch hydrothermale Lösungen (Zentraler Aaregranit). Schweiz. Mineral. Petrogr. Mitt., 64, 67–82.Google Scholar
Mullis, J. (1975) Growth conditions of quartz crystals from Val d'Illiez (Valais, Switzerland). Schweiz. Mineral. Petrogr. Mitt., 55, 419–29.Google Scholar
Mullis, J. (1983) Einschlüsse in Quarzkristallen der Schweizer Alpen und ihre mineralogisch-geologische Bedeutung. Bull. Soc. Fribourg Sci. Nat., 72, 5–19.Google Scholar
Mullis, J. (1996) P-T-t path of quartz formation in extensional veins of the Central Alps. Schweiz. Mineral. Petrogr. Mitt., 76, 159–64.Google Scholar
Mullis, J. and Stalder, H.A. (1987) Salt-poor and saltrich fluid inclusions in quartz from two boreholes in northern Switzerland. Chem. Geol., 61, 263–72.CrossRefGoogle Scholar
Mullis, J., Dubessy, J., Poty, B. and O'Neil, J. (1994) Fluid regimes during late stages of a continental collision: Physical, chemical and stable isotope measurements of fluid inclusions in fissure quartz from a geotraverse through the Central Alps, Switzerland. Geochim. Cosmochim. Acta, 58, 2239–67.CrossRefGoogle Scholar
Oncken, O. (1984) Zusammenhänge in der Strukturgenese des Rheinischen Schiefergebirges. Geol. Rundsch., 73, 619–49.CrossRefGoogle Scholar
Oncken, O. (1988) Aspects of the reconstruction of the stress history of a fold and thrust belt (Rhenish Massif , Federal Republic of Germany). Tectonophysics, 152, 19–40.CrossRefGoogle Scholar
Oncken, O. (1991) Aspects of the structural and paleogeothermal evolution of the Rhenish Massif. Ann. Soc. Geol. Belg., 113, 139–59.Google Scholar
Potter, R.W., Clynne, M.A. and Brown, D.L. (1978) Freezing point depression of aqueous sodium chloride solutions. Econ. Geol., 73, 284–5.CrossRefGoogle Scholar
Poty, B., Stalder, H.A. and Weissbrod, A.M. (1974) Fluid inclusion studies in quartz from fissures of Western and Central Alps. Schweiz. Mineral. Petrogr. Mitt., 54, 717–52.Google Scholar
Ramsay, J.G. (1980) The crack-seal mechanism of rock deformation. Nature, 284, 135–9.CrossRefGoogle Scholar
Ramsay, J.G. and Huber, M.I. (1987) The Techniques of Modern Structural Geology (vol. 2). Academic Press, London.Google Scholar
Roedder, E. (editor) (1984) Fluid inclusions. Reviews in Mineralogy, 12, Mineralogical Society of America, Washington D.C. CrossRefGoogle Scholar
Sandberger, F. (1880) Über die Bildung von Erzgängen mittelst Auslaugung des Nebengesteins. Z. Dt. Geol. Ges., 32, 350–70.Google Scholar
Stalder, H.A. (1964) Petrographische und mineralogische Untersuchungen im Grimselgebiet (Mittleres Aarmassiv). Schweiz. Mineral. Petrogr. Mitt., 44, 187–398.Google Scholar
Stalder, H.A. (1985) Beschreibung der geschützten Mineralkluft Gerstenegg, Grimsel, Bern. Mitteilungen der Naturforschenden Gesellschaft in Bern, 41–60.Google Scholar
Stalder, H.A. and Touray, J.C. (1970) Fensterquarze mit Methan-Einschlüssen aus dem westlichen Teil der schweizeris chen Kalkalpen. Schweiz. Mineral. Petrogr. Mitt., 50, 109–30.Google Scholar
Tröger, W.E. (1982) Optische Bestimmung der gesteinsbildenden Minerale, Teil I, Bestimmungstabellen . Schweizerbart, Stuttgart.Google Scholar
Von Damm, K.L., Bischoff, J.L. and Rosenbauer, R.J. (1991) Quartz solubility in hydrothermal seawater: An experimental study and equation describing quartz solubility for up to 0.5 M NaCl solutions. Amer. J. Sci., 291, 977–1007.CrossRefGoogle Scholar
von Koenigswald, W. and Meyer, W. (editors) (1994) Erdgeschichte im Rheinland. Fossilien und Gesteine aus 400 Millionen Jahren. Pfeil, München.Google Scholar
Wagner, T. and Cook, N.J. (1998) Sphalerite remobilization during multistage hydrothermal mineralization events – examples from siderite-Pb-Zn-Cu-Sb veins, Rheinisches Schieferge birge, Germany. Mineral. Petrol., 63, 223–41.CrossRefGoogle Scholar
Wagner, T. and Cook, N.J. (2000) Late-Variscan antimony mineralisation in the Rheinisc hes Schiefergebirge, NW Germany: Evidence for stibnite precipitation by drastic cooling of high-temperature fluid systems. Mineralium Deposita, 35, 206–22.CrossRefGoogle Scholar
Walshe, J.L. (1986) A six-component chlorite solid solution model and the conditions of chlorite formation in hydrothermal and geothermal systems. Econ. Geol., 81, 681–703.CrossRefGoogle Scholar
Xie, Z. and Walther, J.V. (1993) Quartz solubilities in NaCl solutions with and without wollastonite at elevated temperatures and pressures. Geochim. Cosmochim. Acta, 57, 1947–55.CrossRefGoogle Scholar
Zhang, Y. and Frantz, J.D. (1987) Determination of the homogenization temperatures and densities of supercritical fluids in the system NaCl-KCl-CaCl2-H2O using synthetic fluid inclusions. Chem. Geol., 64, 335–50.CrossRefGoogle Scholar