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Sm-Nd isotopic study of garnets and their metamorphic host rocks

Published online by Cambridge University Press:  03 November 2011

O. van Breemen  and
C. J. Hawkesworth
O. van Breemen
Affiliation:
Isotope Geology Unit, Scottish Universities Research and Reactor Centre, East Kilbride, Glasgow G75 0QU, Scotland.
C. J. Hawkesworth
Affiliation:
Department of Earth Sciences, The Open University, Walton Hall, Milton Keynes, MK7 6AA, England.
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Abstract

In this feasibility study, Sm/Nd and 143Nd/144Nd ratios have been determined on garnets and coexisting mineral and whole-rock phases from a selection of amphibolite facies rocks, granulite facies rocks and an eclogite. In two micaceous schists and an eclogite the distribution coefficient of the Sm/Nd ratio in garnet relative to other phases is in the range 2-3, i.e. comparable to values for phenocrysts in igneous rocks. In two granulite facies rocks the garnets have Sm/Nd distribution coefficients relative to other phases in the range 13-20 and have yielded precise ages.

Garnet from a granulite facies shear zone from the Limpopo belt in southern Africa, of Archaean age, has yielded concordant duplicate ages of 1974±14 Ma and 1988±14 Ma. These results have been interpreted as relating to the last tectonic event in the region, long after the main gneiss-forming event. Garnet from a granulite facies xenolith from a Carboniferous vent in the Midland Valley of Scotland has yielded an age of 356±10 Ma; this is related to the onset of basic magmatism in the region.

Keywords

distribution coefficienteclogitexenolithschistgranulite faciesamphibolite facies
Type
Research Article
Information
Earth and Environmental Science Transactions of The Royal Society of Edinburgh , Volume 71 , Issue 2 , 1980 , pp. 97 - 102
Copyright
Copyright © Royal Society of Edinburgh 1980

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References

Bamford, D., Nunn, K., Prodehl, C. & Jacobs, B. 1977. LISPB III. Upper crustal structure of northern Britain. J GEOL SOC LONDON 133, 481–8.Google Scholar
Brook, M., Powell, D. & Brewer, M. S. 1976. Grenville age for rocks in the Moine of northwestern Scotland. NATURE 260, 515–7.CrossRefGoogle Scholar
Brook, M., Powell, D. & Brewer, M. S. 1977. Grenville events in Moine rocks of the Northern Highlands, Scotland. J GEOL SOC LONDON 133, 489–96.CrossRefGoogle Scholar
Coward, M. P., James, P. R. & Wright, L. 1976. Northern margin of the Limpopo mobile belt, Southern Africa. BULL GEOL SOC AM 87, 601–11.2.0.CO;2>CrossRefGoogle Scholar
De Paolo, D. J. & Wasserburg, G. J. 1976. Nd-isotope variations and petrogenic models. GEOPHYS RES LETT 3, 249–52.CrossRefGoogle Scholar
Dewey, J. F. & Burke, K. C. A. 1973. Tibetan, Variscan and Precambrian basement reactivation: Products of continental collision. J GEOL 81, 683–92.CrossRefGoogle Scholar
Freer, R. 1979. An experimental measurement of cation diffusion in almandine garnet. NATURE 280, 220–2.Google Scholar
Graham, A. M. & Upton, B. G. J. 1978. Gneisses in diatremes, Scottish Midland Valley: petrology and tectonic implications. J GEOL SOC LONDON 135, 219–28.Google Scholar
Hamilton, P. J., Evensen, N. M., O'Nions, R. K. & Tarney, J. 1979. Sm-Nd systematics of Lewisian gneisses: implications for the origin of granulites. NATURE 277, 25–8.Google Scholar
Hamilton, P. J., O'Nions, R. K. & Evensen, N. M. 1977. Sm-Nd dating of Archaean basic and ultrabasic volcanics. EARTH PLANET SCI LETT 36, 263–8.CrossRefGoogle Scholar
Harris, A. L. & Pitcher, W. S. 1975. The Dalradian Supergroup. In Harris, A. L. et al. (eds) A correlation of Precambrian rocks in the British Isles, 52–75. SPEC REP GEOL SOC LONDON 6.Google Scholar
Harrison, W. J. 1978. Rare earth element partitioning between garnets, pyroxenes and melts at low trace element concentration. CARNEGIE INST WASHINGTON YEARB 77, 682–9.Google Scholar
Hawkesworth, C. J. 1976. Rb/Sr geochronology in the Eastern Alps. CONTRIB MINERAL PETROL 54, 225–44.Google Scholar
Hawkesworth, C. J., Moorbath, S., O'Nions, R. K. & Wilson, J. F. 1975. Age relationships between greenstone belts and ‘granites’ in the Rhodesian Archaean craton. EARTH PLANET SCI LETT 25, 251–62.Google Scholar
Hawkesworth, C. J. & Vollmer, R. 1979. Crustal contamination versus enriched mantle: 143Nd/144Nd and87Sr/86Sr evidence from the Italian volcanics. CONTRIB MINERAL PETROL 69, 151–65.Google Scholar
Hawkesworth, C. J., Waters, D. J. & Bickle, M. J. 1975. Plate tectonics in the Eastern Alps. EARTH PLANET SCI LETT 24, 405–13.CrossRefGoogle Scholar
Hickman, M. H. & Wakefield, J. 1975. Tectonic implications of new geochronological data from the Limpopo belt at Pikwe, Bots wana, southern Africa. BULL GEOL SOC AM 86, 1468–72.2.0.CO;2>CrossRefGoogle Scholar
Holland, T. J. B. 1979. High water activities in the generation of high pressure kyanite eclogites of the Tauern window, Austria. J GEOL 87, 1–27.CrossRefGoogle Scholar
Hooker, P., O'Nions, R. K. & Pankhurst, R. J. 1975. Determination of rare-earth elements in U.S.G.S. standard rocks in mixed solvent ion exchange and mass spectrometric isotope dilution. CHEM GEOL 16, 189–96.CrossRefGoogle Scholar
Irving, A. J. & Frey, F. A. 1978. Distribution of trace elements between garnet megacrysts and host volcanic liquids of kimberlite to rhyolitic composition. GEOCHIM COSMOCHIM ACTA 42, 771–88.Google Scholar
Lambert, R.St, J. & McKerrow, W. S. 1976. The Grampian orogeny. SCOTT J GEOL 12, 271–92.Google Scholar
Longman, C. D., Bluck, B. J. & Van Breemen, O. 1979. Ordovician conglomerates and the evolution of the Midland Valley. NATURE 280, 578–81.CrossRefGoogle Scholar
Lugmair, G. W. 1974. Sm-Nd ages: a new dating method (abs). METEORITICS 9, 369.Google Scholar
Lugmair, G. W., Scheinin, N. B. & Marti, K. 1975a. Sm-Nd age and history of Apollo 17 basalt 75075: evidence for early differentiation of the lunar exterior. PROC LUNAR SCI CONF 6, 1419–29.Google Scholar
Lugmair, G. W., Scheinin, N. B. & Marti, K. 1975b. Sm-Nd systematics of the Stannein Meteorite. METEORITICS 10, 447–8.Google Scholar
McCulloch, M. T. & Wasserburg, G. J. 1978. Sm-Nd and Rb-Sr chronology of continental crust formation. SCIENCE 200, 1003–11.CrossRefGoogle ScholarPubMed
McQueen, J. A. & Powell, D. 1977. Relationships between deformation and garnet growth in Moine (Precambrian) rocks of western Scotland. BULL GEOL SOC AM 88, 235–40.2.0.CO;2>CrossRefGoogle Scholar
Magaritz, M. & Hofmann, A. W. 1978. Diffusion of Eu and Gd in basalt and obsidian. GEOCHIM COSMOCHIM ACTA 42, 847–58.CrossRefGoogle Scholar
Misra, N. K. & Venkatsubramanian, U. S. 1977. Strontium diffusionin feldspar — a laboratory study. GEOCHIM COSMOCHIM ACTA 41, 837–8.CrossRefGoogle Scholar
Mysen, B. O. 1978. Experimental determination of crystal-vapour partition coefficients for rare earth elements to 30 kbar pressure. CARNEGIE INST WASHINGTON YEARB 77, 689–95.Google Scholar
Nagasawa, H. 1970. Rare earth concentration in zircon and apatite and their host dacites and granites. EARTH PLANET SCI LETT 9, 359–64.Google Scholar
Notsu, K., Mabuchi, H., Yoshioka, J., Matsuda, J. & Ozima, M. 1973. Evidence of the extinct nuclide 146Sm in ‘Juvinas’ achondrite. EARTH PLANET SCI LETT 19, 29–36.CrossRefGoogle Scholar
O'Nions, R. K., Hamilton, P. J. & Evensen, N. M. 1977. Variations in 143Nd/144Nd and 87Sr/86Sr rations in oceanic basalts. EARTH PLANET SCI LETT 34, 13–22.Google Scholar
Pankhurst, R. J. & Pidgeon, R. T. 1976. Inherited isotope systems and the source region pre-history of early Caledonian granites in the Dalradian series of Scotland. EARTH PLANET SCI LETT 31, 55–68.CrossRefGoogle Scholar
Peach, B. N., Home, J., Woodward, H. B., Clough, C. T., Harker, A. & Wedd, C. B. 1910. The geology of Glenelg, Lochalsh and south-east part of Skye. MEM GEOL SURV SCOTLAND.Google Scholar
Philpotts, J. A. 1978. The law of constant rejection. GEOCHIM COSMOCHIM ACTA 42, 909–20.Google Scholar
Powell, D. 1974. Stratigraphy and structure of the western Moine and the problem of Moine orogenesis. J GEOL SOC LONDON 130, 575–93.Google Scholar
Raheim, A. & Green, D. H. 1975. P, T paths of natural eclogites during metamorphism — a record of subduction. LITHOS 8, 317–26.Google Scholar
Robertson, I. D. M. & Van Breemen, O. 1970. The southern satellite dykes of the Great Dyke, Rhodesia. In Visser, D. J. L. & Gruenewaldt, G. (eds) Symposium on the Bushveld igneous complex and other layered intrusions, 621–44. SPEC PUBL GEOL SOC S AFR 1.Google Scholar
Schnetzler, C. C. & Philpotts, J. A. 1970. Partition coefficients of rare-earth elements between igneous matrix material and rock forming mineral phenocrysts II. GEOCHIM COSMOCHIM ACTA 34, 331–40.CrossRefGoogle Scholar
Shimizu, N. & Kushiro, I. 1975. Partitioning of rare earth elements between garnet and liquid at high pressure: preliminary experiments. GEOPHYS RES LETT 2, 413–6.Google Scholar
Strogen, P. 1974. The sub-Palaeozoic basement in central Ireland. NATURE 250, 562–3.Google Scholar
Tanner, P. W. G. 1971. The Sgurr Beag Slide — a major tectonic break within the Moinian of the western Highlands of Scotland. Q J GEOL SOC LONDON 126, 435–63.Google Scholar
Tarney, J. & Windley, B. F. 1977. Chemistry, thermal gradients and evolution of the lower continental crust. J GEOL SOC LONDON 134, 153–72.CrossRefGoogle Scholar
Upton, B. G. J., Aspen, P., Graham, A. M. & Chapman, N. A. 1976. Pre-Palaeozoic basement of the Scottish Midland Valley. NATURE 260, 517–8.CrossRefGoogle Scholar
Van Breemen, O. & Dodson, M. H. 1972. Metamorphic chronology of the Limpopo Belt, Southern Africa. GEOL SOC AM BULL 83, 2005–18.Google Scholar
Van Breemen, O., Halliday, A. N., Johnson, M. R. W. & Bowes, D. R. 1978. Crustal additions in late Precambrian times. In Bowes, D. R. & Leake, B. E. (eds) Crustal evolution in northwestern Britain and adjacent regions, 81–106. GEOL J SPEC ISSUE 10.Google Scholar
Van Breemen, O., Aftalion, M., Pankhurst, R. J. & Richardson, S. W. 1979. Age of the Glen Dessary syenite, Inverness-shire: diachronous Palaeozoic metamorphism across the Great Glen. SCOTT J GEOL 15, 49–62.CrossRefGoogle Scholar
Whittaker, E. J. W. & Muntus, Y. 1970. Ionic radii for use in geochemistry. GEOCHIM COSMOCHIM ACTA 34, 945–56.Google Scholar
Wood, B. J. 1976. Samarium distribution between garnet and liquid at high pressure. CARNEGIE INST WASHINGTON YEARB. 75, 659–62.Google Scholar
Yardley, B. W. D. 1977. An empirical study of diffusion in garnet. AM MINERAL 62, 793–80.Google Scholar