Hostname: page-component-78c5997874-xbtfd Total loading time: 0 Render date: 2024-11-04T21:54:50.000Z Has data issue: false hasContentIssue false

Zr budgets for metamorphic reactions, and the formation of zircon from garnet breakdown

Published online by Cambridge University Press:  05 July 2018

H. Degeling*
Affiliation:
Department of Geology, Australian National University, ACT 0200, Australia
S. Eggins
Affiliation:
Research School of Earth Sciences, Australian National University, ACT 0200, Australia
D. J. Ellis
Affiliation:
Department of Geology, Australian National University, ACT 0200, Australia
*

Abstract

The construction of zirconium (Zr) budgets for metamorphic reactions in high-grade rocks provides new insight into zircon growth during metamorphism. In this study we target reactions involving garnet, as they enable zircon growth to be related to known pressure and temperature conditions. Two reactions involving the breakdown of Zr-bearing garnet from Rogaland, SW Norway have been investigated in detail, showing contrasting behaviour of Zr, with zircon formation being subject to the solubility of Zr in product phases. In the decompression reaction garnet + sillimanite + quartz → cordierite, Zr released during garnet breakdown cannot be incorporated into the cordierite structure, resulting in zircon nucleation and growth. In contrast, for the reaction garnet + biotite + sillimanite + quartz → osumilite + orthopyroxene + spinel + magnetite, no new zircon growth takes place, despite the garnet involved containing more than double the Zr concentration of the former reaction. In the latter case, all the Zr released by garnet breakdown can be detected in the product phases osumilite and orthopyroxene, thereby preventing growth of new metamorphic zircon. This study highlights the potential for high resolution geochronology in metamorphic rocks by relating zircon growth to specific metamorphic reactions.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2001

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

Bea, F. and Montero, P. (1999) Behaviour of accessory phases and redistribution of Zr, REE, Y, Th and U during metamorphism and partial melting of metapelites in the lower crust: An example from the Kinzigite Formation of Ivrea-Verbano, NW Italy. Geochim. Cosmochim. Acta, 63, 1133–53.CrossRefGoogle Scholar
Bingen, B. and van Breemen, O. (1998) U-Pb monazite ages in amphibolite- to granulite-facies orthogneiss reflect hydrous mineral breakdown reactions: Sveconorwegian Province of SW Norway. Contrib. Mineral. Petrol., 132, 336–53.CrossRefGoogle Scholar
Bingen, B., Austrheim, H. and Whitehouse, M. (2001) Ilmenite as a source for zirconium during high-grade metamorphism? Textural evidence from the Caledonides of W. Norway and implications for zircon geochronology. J. Petrol., 42, 355–75.CrossRefGoogle Scholar
Deer, W.A., Howie, R.A. and Zussman, J. (1992) An Introduction to the Rock-Forming Minerals, 2nd edition. Longman, Essex, UK.Google Scholar
Duschesne, J., Schärer, U. and Wilmart, E. (1993) A 10 Ma period of emplacement for the Rogaland anorthosites, Norway: evidence from U-Pb ages. Terra Abs., 58, 64–.Google Scholar
Eggins, S.M., Rudnick, R.L. and McDonough, W.F. (1998) The composition of peridotites and their minerals: a laser-ablation ICP-MS study. Earth Planet. Sci. Lett., 154, 53–71.CrossRefGoogle Scholar
Falkum, T. (1982) Map Sheet: Mandal, bedrock geology, scale 1:250,000. Norges Geologiske Undersł kelse. Google Scholar
Fraser, G., Ellis, D. and Eggins, S. (1997) Zirconium abundance in granulite-facies minerals, with implications for zircon geochronology in high-grade rocks. Geology, 25, 607–10.2.3.CO;2>CrossRefGoogle Scholar
Green, T.H. (1994) Experimental studies of trace-element partitioning applicable to igneous petrogenesis – Sedona 16 years later. Chem. Geol., 117, 1–36–36.CrossRefGoogle Scholar
Green, T.H., Sie, S.H., Ryan, C.G. and Cousens, D.R. (1989) Proton microprobe determined partitioning of Nb, Ta, Zr, Sr and Y between garnet, clinopyroxene and basaltic magma at high pressure and temperature. Chem. Geol., 74, 201–16.CrossRefGoogle Scholar
Holland, T.J.B., Babu, E.V.S.S.K. and Waters, D.J. (1996) Phase relations of osumilite and dehydration melting in pelitic rocks: a simple thermodynamic model for the KFMASH system. Contrib. Mineral. Petrol., 124, 383–94.CrossRefGoogle Scholar
Holland, T.J.B. and Powell, R. (1990) An enlarged and updated internally consistent thermodynamic dataset with uncertainties and correlations: the system K2O-Na2O-CaO-MgO-MnO-FeO-Fe2O3-Al2O3-TiO2-SiO2-C-H2-O2 . J. Metam. Geol., 8, 89–124.CrossRefGoogle Scholar
Jacques de Dixmude, S. (1978) Géothermométrie comparée de roches du granulite du Rogaland ( méridionale). Bull. Minéral., 101, 57–65.CrossRefGoogle Scholar
Jamtveit, B., Dahlgren, S. and Austrheim, H. (1997) High-grade contact metamorphism of calcareous rocks from the Oslo Rift, Southern Norway. Amer. Mineral., 82, 1241–54.CrossRefGoogle Scholar
Jansen, J.B.H., Blok, R.J.P., Bos, A. and Scheelings, M. (1985) Geothermometry and geobarometry in Rogaland and preliminary results from the Bamble area, S Norway. Pp. 499516 in: The Deep Proterozoic Crust in the North Atlantic Provinces (Tobi, A.C. and Touret, J.L.R., editors). NATO Advanced Studies Institute, 158.CrossRefGoogle Scholar
Jenner, G.A., Foley, S.F., Jackson, S.E., Green, T.H., Fryer, B.J. and Longerich, H.P. (1994) Determination of partition coef. cients for trace elements in high pressure-temperature experimental run products by laser ablation microprobe-inductively coupled plasma-mass spectrometry (LAMICP-MS). Geochim. Cosmochim. Acta, 58, 5099–103.Google Scholar
Kars, H., Jansen, J.B.H., Tobi, A.C. and Poorter, R.P.E. (1980) The metapelitic rocks of the polymetamorphic Precambrian of Rogaland, SW Norway, Part II. Mineral relations between cordierite, hercynite and magnetite within the osumilite-in isograd. Contrib. Mineral. Petrol., 74, 235–44.CrossRefGoogle Scholar
Longerich, H.P., Jackson, S.E. and Günther, D. (1996) Laser ablation inductively coupled plasma mass spectometric transient signal data acquisition and analyte concentration calculation. J. Anal. Atomic Spectrosc., 11, 899–904.CrossRefGoogle Scholar
Maijer, C. and Padget, P. (1987) The Geology of Southernmost Norway; an excursion guide. Norges Geologiske Undersłkelse, Special Publication, 1.Google Scholar
Milton, C., Ingram, B.L. and Blade, L.V. (1961) Kimzeyite, a zirconium garnet from Magnet Cove, Arkansas. Amer. Mineral., 46, 533–48.Google Scholar
Munno, R., Rossi, G. and Tadini, C. (1980) Crystal chemistry of kimzeyite from Stromboli, Aeolian Islands, Italy. Amer. Mineral., 65, 188–91.Google Scholar
Pan, Y. (1997) Zircon- and monazite-forming metamorphic reactions at Manitouwadge, Ontario. Canad. Mineral., 135, 105–18.Google Scholar
Pasteels, P. and Michot, J. (1975) Geochronologic investigation of the metamorphic terrain of southwestern Norway. Norsk Geologisk Tidsskrift, 55, 111–34.Google Scholar
Schärer, U., Wilmart, E. and Duchesne, J. (1996) The short duration and anorogenic character of anorthosite magmatism: U-Pb dating of the Rogaland complex, Norway. Earth Planet. Sci. Lett., 139, 335–50.CrossRefGoogle Scholar
Thompson, A.B. (1976) Mineral reactions in pelitic rocks: II. Calculation of some P-T-X(Fe-Mg) phase relations. Amer. J. Sci., 276, 425–54.CrossRefGoogle Scholar
Tobi, A.C., Hermans, G.A.E.M., Maijer, C. and Jansen, J.B.H. (1985) Metamorphic zoning in the high-grade Proterozoic of Rogaland-Vest Agder, SW Norway. Pp. 477-97 in: The Deep Proterozoic Crust in the North Atlantic Provinces (Tobi, A.C. and Touret, J.L.R, editors). NATO Advanced Studies Institute, 158.CrossRefGoogle Scholar
Vavra, G., Gebauer, D., Schmid, R. and Compston, W. (1996) Multiple zircon growth and recrystallization during polyphase Late Carboniferous to Triassic metamorphism in granulites of the Ivrea Zone (Southern Alps): an ion microprobe (SHRIMP) study. Contrib. Mineral. Petrol., 122, 337–58.CrossRefGoogle Scholar
Westphal, M. and Schumacher, J.C. (1996) The granulite-facies rocks of the Rogaland anorthosite complex in southwestern Norway: new pressuretemperature data and a thermal model. Eur. J. Mineral., 8, 308–(abstract).Google Scholar
Wielens, J.B., Andriessen, P.A.M., Boelrijk, N.A.M., Hebeda, E.H., Priem, H.N.A., Verdurmen, E.A.T. and Verschure, R.H. (1981) Isotope geochronology in the high-grade metamorphic Precambrian of southwestern Norway: new data and reinterpretations. Norges Geologiske Undersł kelse, Bull., 359, 1–30.Google Scholar
Wilson, J.R., Pedersen, S., Berthelsen, C.R. and Jako bsen, B.M. (1977) New light on the Precambrian Holum granite, South Norway. Norsk Geologisk Tidsskrift, 57, 347–60.Google Scholar