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Cu-Fe-U phosphate mineralization of the Hagendorf-Pleystein pegmatite province, Germany: with special reference to laser-ablation inductively-coupled plasma mass spectrometry (LA-ICP-MS) of limonite-cored torbernite

Published online by Cambridge University Press:  05 July 2018

H. G. Dill ,
A. Gerdes  and
B. Weber
H. G. Dill*
Affiliation:
Federal Institute for Geosciences and Natural Resources, P.O. Box 510163 D-30631 Hannover, Germany
A. Gerdes
Affiliation:
Frankfurt University, Institute of Geosciences, Petrology and Geochemistry, Senckenberganlage 28, D-60054 Frankfurt am Main, Germany
B. Weber
Affiliation:
Bürgermeister-Knorr Str. 8, D-92637 Weiden i.d.OPf., Germany
*
E-mail: [email protected]
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Abstract

Iron played a decisive part when uranyl phosphates (‘yellow U ores’) formed during supergene alteration of the aplitic and pegmatitic rocks of the Hagendorf Pegmatite Province. Three different supergene U mineral successions, referred to in the current study as pathways I to III, were identified. Pathway I began with the release of PO42– by the dissolution of rockbridgeite and ended after shortdistance transport under alkaline reducing or slightly acidic oxidizing conditions in the precipitation of bassetite. Pathway II is an advanced form of pathway I that did not stop with the precipitation of bassetite, but progressed by acidic Cu-bearing meteoric waters under oxidizing conditions up to the torbernite precipitation stage. Minor amounts of Mn or Ca may have led to a deviation from the normal pathway into the stability fields of lehnerite or autunite, respectively, both of which may occur either as solid solution series or in a layered intergrowth with torbernite. Limonite-cored torbernite has been described for the first time and only exists in pathway III. Unlike its counterpart pathways I and II, which appeared at the end of a complex polystage element recycling process of secondary Fe phosphates under fluctuating redox and pH conditions, limonite-cored torbernite resulted from a monostage transformation of primary ‘black Fe-U ore minerals’ under strongly oxidizing conditions and short-distance element transport. These restricted physicochemical conditions caused the immediate stabilization of the Fe-U-P system and by doing so the U-Pb ratios of the black ore progenitor were well preserved in the limoniticc ore. Torbernite was analysed for U, Th and Pb isotopes by laser ablation inductively coupled plasma mass spectrometry techniques. For one domain the data yielded a formation age of 4.55±0.02 Ma, which corresponds to Miocene-Pliocene weathering and geomorphological processes in the study area. A second domain gave a discordia with an upper intercept age of 549±12 Ma, interpreted to represent a thermal event at the Precambrian-Cambrian boundary. Ferrocolumbite is found exclusively in the mineralization of pathway III. Due to the proximity of ferrocolumbite to torbernite, limonite-cored torbernite probably inherited the 549 Ma age from ferrocolumbite during supergene alteration.

Keywords

torbernitegoethiteICP-MSlaser ablation techniquesupergene alterationelement recyclingHagendorfGermany
Type
Research Article
Information
Mineralogical Magazine , Volume 71 , Issue 4 , August 2007 , pp. 371 - 387
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2007

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References

Aftalion, M., Bowes, D.R. and Vrána, S. (1989) Early Carboniferous uranium–lead zircon age for garnetiferous, perpotassicgranulites, Blansky les Massif, Czechoslovakia. Neues Jahrbuch für Mineralogie Monatshefte, 4, 145–152.Google Scholar
Borger, H., Burger, D. and Kubiniok, J. (1993) Verwitterungsprozesse und deren Wandel im Zeitraum Tertiär–Quartär. Zeitschrift für Geomorphologie N.F. Hauptbände, 37, 129–143.Google Scholar
Carl, C. and Dill, H.G. (1983) Uranium disequilibria and modern redistribution phenomena in alteration zones in the Höhensteinweg uranium occurrence. Uranium, 1, 113–125.Google Scholar
Chakrabarti, A.K. (1988) An appraisal of the mineral potential of the Somali Democratic Republic: Mogadishu, Somalia. The United Nations Revolving Fund for Natural Resources Exploration, 230 pp.Google Scholar
Dall’aglio, M., Gragnani, R. and Locardi, E. (1974) Geochemical factors controlling the formation of the secondary minerals of uranium. I.A.E.A., Proceedings of the Symposium on the Formation of Uranium Ore Deposits, Athens.Google Scholar
Dill, H.G. (1983) On the formation of the vein–type uranium ‘yellow ores’ from the Schwarzach area (NE Bavaria, Germany) and on the behaviour of P, As, V and Se during supergene processes. International Journal of Earth Sciences/ Geologische Rundschau, 72, 955–980.Google Scholar
Dill, H.G. (1985) Genesis and timing of secondary uranium mineralization in Northern Bavaria (F.R. Germany) with special reference to geomorphology. Uranium, 2, 1–16.Google Scholar
Dill, H.G., Melcher, F., Fuessl, M. and Weber, B. (2007) The origin of rutile–ilmenite aggregates (‘nigrine’) in alluvial–fluvial placers of the Hagendorf pegmatite province, NE Bavaria, Germany. Mineralogy and Petrology, 89, 133–158.CrossRefGoogle Scholar
Fayek, M., Harrison, T.M., Ewing, R.C., Grove, M. and Coath, C.D. (2002) O and Pb isotopicanalyses of uranium minerals by ion microprobe and U–Pb ages from the Cigar Lake deposit. Chemical Geology, 185, 205–225.CrossRefGoogle Scholar
Fiala, J., Fuchs, G. and Wendt, J.I. (1995) Stratigraphy. Pp. 417–428 in: Pre–Permian Geology of Central and Eastern Europe (Dallmeyer, R.D., Franke, W. and Weber, W., editors). Springer, Berlin, Heidelberg.,Google Scholar
Forster, A. (1965) Erläuterungen zur Geologischen Karte von Bayern 1:25000 Blatt Vohenstraus/ Frankenreuth. GLA Munich, 174 pp.Google Scholar
Forster, A., Strunz, H. and Tennyson, Ch. (1967) Die Pegmatite des Oberpfälzer Waldes, insbesondere der Pegmatit von Hagendorf–Süd. Aufschluß, 16, 137–198.Google Scholar
Franke, W. (1989) The geological framework of the KTB drill site, Oberpfalz. Pp. 37–54 in: The German Continental Deep Drilling Program (KTB) (Emmermann, R. and Wohlenberg, J., editors). Springer, Heidelberg, Berlin, New York.Google Scholar
Gerdes, A. and Zeh, A. (2006) Combined U–Pb and Hf isotope LA–(MC–)ICP–MS analyses of detrital zircons: Comparison with SHRIMP and new constraints for the provenance and age of an Armorican metasediment in Central Germany. Earth and Planetary Science Letters, 249, 47–62.CrossRefGoogle Scholar
Glodny, J., Grauert, B., Fiala, J., Vejnar, Z. and Krohe, A. (1998) Metapegmatites in the western Bohemian massif: ages of crystallization and metamorphic overprint, as constrained by U–Pb zircon, monazite, garnet, columbite and Rb–Sr muscovite data. International Journal of Earth Sciences/ Geologische Rundschau, 87, 124–134.Google Scholar
Horstwood, M.S.A., Foster, G.L., Parrish, R.R., Noble, S.R. and Nowell, G.M. (2003) Common–Pb corrected in situ U–Pb accessory mineral geochronology by LA–MC–ICP–MS. Journal of Analytical Atomic Spectrometry, 18, 837–846.CrossRefGoogle Scholar
Ilani, S. and Strull, A. (1988) Uranium mineralization in the Judean Desert and in the northern Negev, Israel. Ore Geology Reviews, 4, 305–314.Google Scholar
Jackson, S.E., Pearson, N.J., Griffin, W.L. and Belousova, E.A. (2004) The application of laser ablation–inductively coupled plasma–mass spectrometry to in situ U–Pb zircon. Geochronology, 211, 47–69.Google Scholar
Janouek, V., Gerdes, A., Vrána, S., Finger, F., Erban, V., Friedl, G. and Braithwaite, C.J.R. (2006) Lowpressure granulites of the Liov Massif, southern Bohemia: Viséan metamorphism of late Devonian plutonica rc rocks. Journal of Petrology, 47, 705–744.Google Scholar
Keay, S. and Vasconcelos, P. (2000) The potential use of secondary uranium minerals in weathering geochronology. 9th International Conference on Fission Track Dating and Thermochronology, Lorne. Geological Society of Australia Abstracts, 58, 201–202.Google Scholar
Lenz, H., Wendt, I. and Gudden, H. (1962) Altersbestimmungen an sekundären Uranmineralien aus dem Fichtelgebirge und dem nördlichen Oberpfälzer Wald nach der Pb/U Methode. Geologica Bavarica, 49, 124–133.Google Scholar
Locock, A.J. and Burns, P.C. (2003) Crystal structures and synthesis of the copper–dominated members of the autunite and meta–autunite groups: Torbernite, zeunerite, meta–torbernite and meta–zeunerite. The Canadian Mineralogist, 41, 489–502.CrossRefGoogle Scholar
Louis, H. (1984) Zur Reliefentwicklung der Oberpfalz. Relief, Boden, Paläoklima, 3, 1–66.Google Scholar
Ludwig, K.R. (2001) Users Manual for Isoplot/ex rev. 2.49: a Geochronological Toolkit for Microsoft Excel. Special Publication 1a, Berkeley Geochronology Center, 1–56 pp.Google Scholar
Mann, A.W. and Deutscher, R.L. (1978) Genesis principles for the precipitation of carnotite in calcrete drainages in Western Australia. Economic Geology, 73, 1724–1737.CrossRefGoogle Scholar
Melcher, F., Sitnikova, M.A., Oberthür, T., Henjes– Kunst, F., Gerdes, A., Brätz, H. and Davis, D.W. (2007) ‘Coltan’ (columbite–tantalite ores): Fingerprinting the source by combined mineralogical and geochemical methods. Pp. 1485–1488 in: Digging Deeper (Andrew, C.J. et al., editors). Proceedings of the Ninth Biennial SGA Meeting, Dublin, vol. 2. Société pour Géologie Appliqué.Google Scholar
Meyer, F.M., Kolb, J., Skallaris, G.A. and Gerdes, A. (2006) New ages from the Mauritanides: Recognition of Archean IOCG mineralization at Guelb Moghrein, Mauritania. Terra Nova, 18, 345–352.Google Scholar
Mücke, A. (1988) Lehnerit, Mn[UO2|PO4]2.8H2O, ein neues mineral aus dem pegmatit von Hagendorf/ Oberpfalz. Aufschluß, 39, 209–217.Google Scholar
Nägele, M. (1982) Orientierte Verwachsungen von Torbernit und Autunit von Hagendorf–Süd. Lapis, 7, 38.Google Scholar
Stacey, J.S. and Kramers, J.D. (1975) Approximation of terrestrial lead isotope evolution by a two–stage model. Earth and Planetary Science Letters, 26, 207–221.CrossRefGoogle Scholar
Strunz, H. (1961) Epitaxie von Uraninit auf Columbit. Aufschluß, 12, 81–84.Google Scholar
Strunz, H., Tennyson, C. and Mücke, A. (1976) Miner a l i e n von Hagendorf/Ostbayern. Fortschrittsbericht 1976. Aufschluß, 27, 329–340.Google Scholar
Walenta, K. (1977) Neue Funde sekundärer Uranmineralien im mittleren und nördlichen Schwarzwald. Aufschluß, 28, 177–188.Google Scholar
Weaver, C.E. (1989) Clays, muds, and shales. Developments in Sedimentology, 44, 1–819.Google Scholar
Wright, H.D. and Emerson, D.O. (1957) Distribution of secondary uranium minerals in the W. Wilson deposit, Boulder Batholith, Montana. Economic Geology, 52, 36–59.CrossRefGoogle Scholar