Abstract
The specularite deposit at Waldenstein is an epigenetic replacement/vein-type hematite mineralization with distinct alteration zones. It is situated in highly metamorphosed schists and, gneisses of the Koralm Crystalline Complex. Sericitization and chloritization are strictly bound to this alteration and occur within a few meters of the hematite veins. Radiometric dating of the sericitization and the implicity of the mineralization yield a Middle Eocene age. Petrographic evidence proves an early, relatively reduced paragenesis (magnetite, ilmenite) being partly replaced by hematite and chlorite during the main phase of ore formation. Fluid inclusion and stable isotope investigations indicate that formation temperatures were approximately 300°C during the main stage and decreased to 200°C in the latest stage of the hydrothermal event. The H-isotope compositions of chlorites and of fluid inclusions in quartz indicate the influence of seawater. This also explains the high salinities determined by fluid inclusion studies (20–30% NaCl equiv.). According to the genetic model presented in this paper the hydrothermal activity started when the deformation accompanying the uplift of the Koralm Crystalline Complex passed from a ductile to brittle regime (Middle Eocene). The brittle faults acted as channelways for rising, deep fluids, probably of metamorphic origin. Temperature differences between the different uplifting crustal segments supported fluid circulation. Precipitation of the ore occurred at shallow crustal levels where the hydraulic regime was dominated by seawater, and oxidation of the original reducing fluids took place.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Awad IMA (1983) The Waldenstein specularite deposit, Carinthia, Austria: geology, metamorphism and genesis. Unveröff Diss Montanuniv Leoben, 222 S
Borisenko AS (1977) Study of the salt composition of solutions of gas-liquid inclusions in minerals by the cryometric method. Geologiya i Geofizika 18/8:16–27
Clar E, Meixner H (1981) Die grundlegenden Beobachtungen zur Entstehung der Eisenspatlagerstätten von Hüttenberg. Carinthia II 171/91:55–92
Clayton RN, Mayeda T (1963) The use of bromine pentafluoride in the extraction of oxygen from oxides and silicates for isotopic analysis. Geochim Cosmochim Acta 27:43–52
Craw D, Koons PO (1989) Tectonically induced hydrothermal activity and gold mineralization adjacent to major fault zones. Econ Geol Monogr 6:471–478
Crawford ML, FILER J, Wood C (1979) Saline fluid inclusions associated with retrograde metamorphism. Bull Minéral 102:562–568
Frank W (1987) Evolution of the Austroalpine elements in the Cretaceous. In: Flügel HW, Faupl P (eds) Geodynamics of the Eastern Alps. Deuticke, Vienna, pp 379–406
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 Graz:263–293
Friedrich O (1929) Die Siderit-Eisenglimmerlagerstätte von Waldenstein in Ostkärnten. Berg Hüttenm Jb 77:131–145
Graham CM, Viglino JA, Harmon RS (1987) Experimental study of hydrogen-isotope exchange between aluminous chlorite and water and of hydrogen diffusion in chlorite. Am Mineral 72:566–579
Günther M (1990) Flüssigkeitseinschlüsse und geologisches Umfeld zentralafrikanischer Sn-, W- und Au-Lagerstätten (Rwanda und Burundi). Bswg Geol Paläontol Diss 11, Braunschweig
Hoefs J (1987) Stable Isotope Geochemistry. 3rd edn. Springer, New York, 140 pp
Hollister LS, Crawford ML (1981) Fluid Inclusions: Applications to Petrology. Short Course Handbook 6. Min Assoc Can, 305
Jung G (1982) Geologische und geochronologische Untersuchungen des Metamorphoseablaufes in Glein-, Stub- und Koralpe. PhD Thesis (unpubl), Univ Vienna:180 pp
Morauf W (1980) Die permische Differentiation und die alpidische Metamorphose des Granitgneises von Wolfsberg, Koralpe, SE-Ostalpen, mit Rb-Sr- und K-Ar-Isotopenbestimmungen. TMPM 27:169–185
Morauf W (1981) Rb-Sr- und K-Ar-Isotopen-Alter an Pegmatiten aus der Kor- und Saualpe, SE-Ostalpen, Österreich. TMPM 28:113–129
Morauf W (1982) Rb-Sr- und K-Ar-Evidenz für eine intensive alpidische Beeinflussung der Paragesteine in Kor- und Saualpe, SE-Ostalpen, Österreich. TMPM 29:255–282
Neubauer F, Genser J (1990) Architektur und Kinematik der östlichen Zentralalpen — eine Übersicht. Mitt Naturwiss Ver Steiermark 120:203–219
Nicholls J, Crawford ML (1985) Fortran programs for calculating of fluid properties from microthermometric data on fluid inclusions. Comput Geosci 11/5:619–645
Prochaska W, Bechtel A, Klötzli U (1992) Phyllonite formation and alteration of gneisses in shear zones (Gleinalmkristallin, Eastern Alps/Austria). Mineral Petrol 45:195–216
Richter R, Hoernes S (1988) The application of the increment method in comparison with experimentally derived and calculated O-isotope fractionations. Chem Erde 48:1–18
Schulz O (1986) Die ostalpinen Lagerstätten mineralogischer Rohstoffe in der Sicht neuer Forschungsergebnisse. Arch Lagerstforsch Geol BA 7:257–287
Schütze H (1980) Der Isotopenindex — Eine Inkrementenmethode zur näherungsweisen Berechnung von Isotopenaustauschgleichgewichten zwischen kristallinen Substanzen. Chem Erde 39:321–334
Shepherd T, Rankin AH, Alderton DHM (1985) A Practical Guide to Fluid Inclusions Studies. Blackie, Glasgow, 239 pp
Sterner S, Hall DL, Bodnar RJ (1988) Synthetic fluid inclusions. V. Solubility reactions in the system NaCl-KCl-H2O under vapor-saturated conditions. Geochim Cosmochim Acta 52:989–1005
Suzuoki T, Epstein S (1976) Hydrogen isotope fractionation between OH-bearing minerals and water. Geochim Cosmochim Acta 40:1229–1240
Sverjensky DA (1984) Europium redox equilibria in aqueous solution. Earth Planet Sci Lett 67:70–78
Thöni M, Jagoutz E (1992) Some new aspects of dating eclogites in orogenic belts: Sm-Nd, Rb-Sr, and Pb-Pb isotopic results from the Austroalpine Saualpe and Koralpe type-locality (Carinthia/Styria, southeastern Austria). Geochim Cosmochim Acta 56:347–368
Tornquist A (1929) Die Vererzungsperioden in den Ostalpen. Metall Erz 26/10:241–246
Wood SA (1990) The aqueous geochemistry of the rare-earth elements and yttrium. 2. theoretical predictions of speciation in hydrothermal solutions to 350°C at saturation water vapor pressure. Chem Geol 88:99–125
Zhang YG, Frantz JD (1987) Determination of the homogenisation temperatures and densities of supercritical fluids in the system NaCl-KCl-CaCl2-H2O using synthetic fluid inclusions. Chem Geol 64:335–350
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Prochaska, W., Pohl, W., Belocky, R. et al. Tertiary metallogenesis in the Eastern Alps: the Waldenstein hematite deposit (Austria). Geol Rundsch 84, 831–842 (1995). https://doi.org/10.1007/BF00240571
Issue Date:
DOI: https://doi.org/10.1007/BF00240571