Abstract
The carbon and oxygen isotopic composition of Fe-carbonate ore and its calcitic to dolomitic Devonian host rocks at the Steirischer Erzberg siderite deposit (Greywacke zone, Upper Austroalpine Unit) were determined in order to constrain the source and nature of the Fe-rich mineralizing fluid. The δ 18O-values obtained for various Fe-carbonate generations and the carbonate host lie within a similar range between + 14.6 and + 21.6‰ (V-SMOW). No good correlation exists between the relative ages of the carbonate phases and their O isotopic composition. The variation in δ 18O-values is due to metamorphic recrystallization with locally variable fluid/rock ratios. The average δ 13C-value of the carbonate host is +0.5 ± 1.2‰ (PDB) which corresponds well to worldwide Phanerozoic marine carbonate values. The first Fecarbonate generation has slightly lower δ 13C-values, on average -1.4 ± 0.8‰ (PDB). Recrystallization of both the carbonate host minerals and the ankerite/siderite led to significantly lower δ 13C-values of -4.2 ± 0.6‰ and-4.7 ± 0.7‰, respectively. Within the basal breccia of the post-Hercynian transgression series matrix calcite/ dolomite shows an average δ 13C-value of -2.9 ± 0.7‰, and matrix siderite/ankerite an average value of-4.1 ± 0.4‰. These data, together with Sr isotope data published previously, strongly support a late-diagenetic or epigenetic first Fe-mineralization from convecting formation waters. They ascended along extension faults and were driven by an increased heat flow caused by crustal thinning during a Devonian rifting phase that initiated the separation of the Noric terrane from Africa. A potential source of the Fe could have been the underlying Ordovician acid volcanics. Regional metamorphism related to collision tectonics in the Late Carboniferous (Hercynian) and later during the Alpine orogeny, caused intensive recrystallization and partial mobilization of the various carbonate phases.
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References
Aharon, P. (1988) A stable-isotope study of magnesites from the Rum Jungle uranium field, Australia: implications for the origin of strata-bound massive magnesites. Chemical Geology 69:127–145
Beran, A. (1979) Die Stellung der Ankeritgesteine im Rahmen der Genese von Sideritlagerstätten der östlichen Grauwackenzone. Tscherm. Min. Petr. Mitt. 26:217–233
Beran, A., Thalmann, F. (1978) Der Bergbau Radmer-Buchegg-ein Beitrag zur Genese alpiner Sideritlagerstätten. Tscherm. Min. Petr. Mitt. 25:287–303
Carothers, W.W., Adami, L.H., Rosenbauer, R.J. (1988) Experimental oxygen isotope fractionation between siderite-water and phosphoric acid liberated CO2-siderite. Geochim. Cosmochim. Acta 52:2445–2450
Craig, H. (1957) Isotopic standards for carbon and oxygen and correction factors for mass-spectrometric analysis of carbon dioxide. Geochim. Cosmochim. Acta 12:133–149
Frank, W., Esterlus, M., Frey, I., Jung, G., Krohe, A., Weber, J. (1983) Die Entwicklungsgeschichte von Stub- und Koralpenkristallin und die Beziehung zum Grazer Paläozoikum. Jber: 1982, Hochschulschwerpunkt S15:263–293, Graz
Friedman, I., O'Neil, J.R. (1977) Compilation of stable isotope fractionation factors of geochemical interest. In: Fleischer, M. (ed.) Data of Geochemistry, 6th edn. U.S. Geol. Surv. Prof. Pap. 440-KK
Frimmel, H.E. (1988) Strontium isotopic evidence for the origin of siderite, ankerite and magnesite mineralizations in the Eastern Alps. Mineral. Deposita 23:268–275
Frimmel, H.E. (1992) Isotopic fronts in hydrothermally mineralized carbonate rocks. Mineral. Deposita 27:257–267
Frisch, W., Neubauer, F. (1989) Pre-Alpine terranes and tectonic zoning in the eastern Alps. In: Dallmeyer, R.D. (ed.) Terranes in the Circum-Atlantic Paleozoic Orogens, Geol. Soc. Am. Spec Pap. 230:91–100
Haditsch, J.G., Mostler, H. (1979) Genese und Altersstellung der Magnesitlagerstätten in den Ostalpen. Verh. Geol. Bundesanst, Vienna 1978 (3): 357–367
Hoefs, J. (1987) Stable isotope geochemistry, 3rd. edn. Springer, Berlin
Hollemann-Wiberg (1985) Lehrbuch der anorganischen Chemie, Heidelberg New York, de Gruyter, Berlin, New York
Kohlrausch, F. (1956) Praktische Physik, Vol. 2. Teubner, Stuttgart
Meixner, H. (1953) Mineralogische Beziehungen zwischen Spatmagnesit und Eisenspatlagerstätten der Ostalpen. Radex-Rundsch, Radenthein 1953:445–458
Moore, S.E., Ferrel, R.E., Ahron, P. (1992) Diagenetic siderite and other ferroan carbonates in a modern subsiding marsh sequence. J. Sedim. Petrol. 62: 357–366
Mostler, H. (1984) An jungpaläozoischen Karst gebundene Vererzungen mit einem Beitrag zur Genese der Siderite des Steirischen Erzberges. Geol. Paläont. Mitt. Innsbruck, Innsbruck 13 (4): 97–111
Mozley, P.S. (1989) Relations between depositional environment and the elemental composition of early diagenetic siderite. Geology 17:704–706
Mozley, P.S., Carothers, W.W. (1992) Elemental and isotopic compositions of siderite in the Kuparuk Formation, Alaska: effect of microbial activity and water/sediment interaction on early porewater chemistry. J. Sedim. Petrol. 62:681–692
Ohomoto, H. (1972) Systematics of sulfur and carbon isotopes in hydrothermal ore deposits. Econ. Geol. 67:551–578
Ohomoto, H., Rye, R.O. (1979) Isotopes of sulfur and carbon. In: Barnes, H.L., (ed.) Geochemistry of hydrothermal ore deposits, 2nd edn. Wiley, New York, pp. 507–567
Parkhurst, D.L., Thorstenson, D.C., Plummer, L.N. (1980) PHREEQE-a computer program for chemical calculations. US Geol. Surv. Water Resources Inv., Washington D.C. 80–90:210 PP
Rosenbaum, J., Sheppard, S.M.F. (1986) An isotopic study of siderites, dolomites and ankerites at high temperatures. Geochim. Cosmochim. Acta. 50:1147–1150
Schönlaub, H.P. (ed.) (1977) Exkursionsführer Nördliche Grauwackenzone (Eisenerzer Alpen). Geol. Bundesamt, Wien
Schramm, J.M. (1977) Über die Verbreitung epi- und anchimetamorpher Sedimentgesteine in der Grauwackenzone und in den Nördlichen Kalkalpen (Österreich)-ein Zwischenbericht. Geol. Paläont. Mitt. Innsbruck, Innsbruck 7 (2):3–20
Schroll, E., Papesch, W., Dolezel, P. (1986) Beitrag der C- und O-Isotopenanalyse zur Genese ostalpiner sideritvorkommen. Mitt. Österr. Geol. Ges. 78:181–191
Schulz, H.D. (1990) Hydrologie. Sommerkurs Universität Bremen, Bremen
Sheppard, S.M.F. (1986) Characterization and isotopic variations in natural waters. In: Valley, J.W., Taylor, H.P., O'Neil, J.R. (eds.) Stable isotopes in high temperature geological processes. Rev. Mineral. 16:165–181
Thalmann, F. (1974) Probleme der Abbauplanung und Qualitätssteuerung am Steirischen Erberg in Abhängigkeit von den geologisch-mineralogischen Verhältnissen. Mitt. Geol. Ges. Wien, Vienna 66–67:245–263
Thalmann, F. (1979) Zur Eisenspatvererzung in der nördlichen Grauwackenzone am Beispiel des Erzberges bei Eisenerz und Radmer/Buckeck. Verh. Geol. Bundesamt., Vienna 1978 (3):479–489
Trusdell, A.H. (1974) Oxygen isotope activities and concentrations in aqueous salt solutions at elevated temperatures-consequences for isotope geochemistry. Earth Planet. Sci. Lett. 23:387–396
Valley (1986) Stable isotope geochemistry of metamorphic rocks. In: Valley, J.W., Taylor, H.P., O'Neil, J.R. (eds.) Stable isotopes in high temperature geological processes. Rev. Mineral. 16:445–486
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Laube, N., Frimmel, H.E. & Hoernes, S. Oxygen and carbon isotopic study on the genesis of the Steirischer Erzberg siderite deposit (Austria). Mineral. Deposita 30, 285–293 (1995). https://doi.org/10.1007/BF00196364
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DOI: https://doi.org/10.1007/BF00196364