Hostname: page-component-78c5997874-xbtfd Total loading time: 0 Render date: 2024-11-10T17:28:00.316Z Has data issue: false hasContentIssue false
  • English
  • Français

Metamorphic development of cordierite-amphibole rocks and mica schists in the vicinity of the Outokumpu ore deposit, Finland

Published online by Cambridge University Press:  03 November 2011

P. J. Treloar ,
T. J. Koistinen  and
D. R. Bowes
P. J. Treloar
Affiliation:
Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ, England.
T. J. Koistinen
Affiliation:
Exploration Department, Outokumpu Oy, 83500 Outokumpu, Finland.
D. R. Bowes
Affiliation:
Department of Geology, University of Glasgow, Glasgow G 12 8QQ, Scotland.
Get access Rights & Permissions [Opens in a new window]

Abstract

Analysed compositions of coexisting phases from cordierite-amphibole-bearing rocks (cordierite-orthoamphibole-cummingtonite-garnet-staurolite-spinel-opaque ores) and mica schists (garnet-staurolite-biotite-muscovite-plagioclase-andalusite-quartz) have been used in conjunction with experimentally determined equilibria to estimate pressures and temperatures of metamorphism for the rocks of the Outokumpu district. The data do not determine a single point in P-T space, but bracket an area such that T ≈ 600 ± 50°C and P ≈ 3·5 ± 1 kb. These conditions represent the maximum temperature attained by the rocks, and the associated sulphide ore bodies, during the Svecokarelian orogeny and are consistent with a regional palaeogeotherm of c. 50°C/km.

Assessment of the composition of the coexisting phases in the cordierite-amphibole-bearing rocks, particularly the Fe-Mg-bearing phases, indicates that it is unlikely that either iron or magnesium was mobile during metamorphism and that the equilibrium assemblage represents essentially isochemical metamorphism of a rock composition that predates the metamorphism. A similar genesis is considered likely for the cordierite-anthophyllite rocks of Orijärvi in southern Finland which forms the basis of the classic statement of the magnesium-metasomatism hypothesis.

Keywords

anthophyllitebiotitecoexisting mineralscummingtonitegarnetgedriteisochemicalmagnesium-metasomatismmineral chemistryP-T conditionsreactionstaurolitestockworkSvecokarelian orogeny.
Type
Research Article
Information
Earth and Environmental Science Transactions of The Royal Society of Edinburgh , Volume 72 , Issue 3 , 1981 , pp. 201 - 215
Copyright
Copyright © Royal Society of Edinburgh 1981

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

Bird, G. W. & Fawcett, J. J. 1973. Stability relation of Mg-chlorite-muscovite and quartz between 5 and 10 kb water pressure. J PETROL 14, 415–28.CrossRefGoogle Scholar
Bogdanov, A. A., Gorbunov, G. I., Gorskij, I. I., Unksov, V. A. & Shatalov, E. T. 1967. Otserednaja sessija Komissii po geologitseskoi karte Mira Mezdunarodnogo geologitseskogo Kongressa. SOV GEOL 3, 130–8.Google Scholar
Bohlen, S. R. & Essene, E. J. 1980. Evaluation of co-existing garnet-biotite garnet-clinopyroxene and other Mg-Fe exchange thermometers in Adirondack granulites: summary. BULL GEOL SOC AM 91, 107–9.2.0.CO;2>CrossRefGoogle Scholar
Bowes, D. R. 1976. Tectonics in the Baltic Shield in the period 2000–1500 million years ago. ACTA GEOL POL 26, 355–76.Google Scholar
Bowes, D. R. 1980. Correlation in the Svecokarelides and a crustal model. In Mitrofanov, F. P. (ed.) Principles and criteria of subdivision of Precambrian in mobile zones, 294–303. Leningrad: Nauka.Google Scholar
Bowes, D. R. & Gaál, G. 1981. Precambrian record of the eastern North Atlantic Borderlands. In Kerr, J. W. & Fergusson, A. J. (eds). Geology of the North Atlantic Borderlands, 31–55. MEM CAN SOC PET GEOL 7.Google Scholar
Campbell, D. S. 1978. Structural and metamorphic studies in the Svecokarelides, Tampere, Finland. Unpublished Ph.D. Thesis, Glasgow University.Google Scholar
Campbell, D. S. 1980. Structural and metamorphic development of migmatites in the Svecokarelides, near Tampere, Finland. TRANS R SOC EDINBURGH EARTH SCI 71, 185–200.CrossRefGoogle Scholar
Campbell, D. S., Treloar, P. J. & Bowes, D. R. 1979. Metamorphic history of staurolite-bearing schists from the Svecokarelides, near Heinävaara, eastern Finland. GEOL FÖREN STOCKHOLM FÖRH 101, 105–18.CrossRefGoogle Scholar
Chinner, G. A. & Fox, J. S. 1974. The origin of cordierite-anthophyllite rocks in the Lands End aureole. GEOL MAG 111, 397–408.CrossRefGoogle Scholar
Droop, G. T. R. & Treloar, P. J. 1981. Pressures of metamorphism in the thermal aureole of the Etive Granite Complex. SCOTT J GEOL 17, 85–102.CrossRefGoogle Scholar
Eskola, P. 1914. On the petrology of the Orijärvi region in southwestern Finland. BULL COMM GEOL FINL 40, 1–279.Google Scholar
Eskola, P. 1933. On the chrome minerals of Outokumpu. BULL COMM GEOL FINL 103, 26–44.Google Scholar
Ferry, J. M. & Spear, F. S. 1978. Experimental calibration of the partitioning of Fe and Mg between biotite and garnet. CONTRIB MINERAL PETROL 66, 113–7.CrossRefGoogle Scholar
Fletcher, C. J. N. & Greenwood, H. J. 1979. Metamorphism and structure of Penfold Creek area, near Quesnal Lake, British Columbia. J PETROL 20, 743–94.CrossRefGoogle Scholar
Gaál, G., Koistinen, T. & Mattila, E. 1975. Tectonics and stratigraphy of the vicinity of Outokumpu, North Karelia, Finland. BULL GEOL SURV FINL 271, 1–67.Google Scholar
Ganguly, J. 1972. Staurolite stability and related parageneses: theory, experiments and application. J PETROL 13, 335–65.CrossRefGoogle Scholar
Gittos, M. F., Lorimer, G. W. & Champness, P. E. 1976. The phase distribution in some exsolved amphiboles. In Wenk, H. R.et al. (eds) Electron microscopy in Mineralogy, 238–47. Berlin: Springer-Verlag.CrossRefGoogle Scholar
Grieve, R. A. F. & Fawcett, J. J. 1974. The stability of chloritoid below 10 kb . J PETROL 15, 113–39.CrossRefGoogle Scholar
Helgeson, H. C., Delany, J. M., Nesbitt, H. W. & Bird, D. K. 1978. Summary and critique of the thermodynamic properties of rock forming minerals. AM J SCI 278A, 1–229.Google Scholar
Holdaway, M. J. 1971. Stability of andalusite and the aluminum silicate phase diagram. AM J SCI 271, 97–131.CrossRefGoogle Scholar
Holdaway, M. J. & Lee, S. M. 1977. Fe-Mg cordierite stability in high grade pelitic rocks based on experimental, theoretical and natural observations. CONTRIB MINERAL PETROL 63, 175–98.CrossRefGoogle Scholar
Huhma, A. & Huhma, M. 1970. Contribution to the geology and geochemistry of the Outokumpu region. BULL GEOL SOC FINL 42, 57–88.CrossRefGoogle Scholar
James, R. S., Grieve, R. A. F. & Pauk, L. 1978. Petrology of cordierite-anthophyllite geneisses and associated mafic and pelitic gneisses at Manitouwadge, Ontario. AM J SCI 278, 41–63.CrossRefGoogle Scholar
Koistinen, T. J. 1981. Structural evolution of an early Proterozoic stratabound Cu-Co-Zn deposit, Outokumpu, Finland. TRANS R SOC EDINBURGH EARTH SCI 72, 115–58.CrossRefGoogle Scholar
Mueller, R. F. 1973. System CaO-MgO-FeO-SiO2-C-H2-O2: some correlations from nature and experiment. AM J SCI 273, 152–70.CrossRefGoogle Scholar
Peltola, E. 1978. Origin of Precambrian copper sulfides of the Outokumpu district, Finland. ECON GEOL 73, 461–77.CrossRefGoogle Scholar
Richardson, S. W. 1968. Staurolite stability in a part of the system Fe-Al-Si-O-H. J PETROL 9, 467–88.CrossRefGoogle Scholar
Richardson, S. W., Gilbert, M. C. & Bell, P. M. 1969. Experimental determination of kyanite-andalusite and andalusite-sillimanite equilibria; the aluminium silicate triple point. AM J SCI 267, 259–72.CrossRefGoogle Scholar
Robinson, P. & Jaffe, H. W. 1969. Chemographic exploration of amphibole assemblages from central Massachusetts and southwestern New Hampshire. MINERAL SOC SPEC PAP 2, 251–74.Google Scholar
Robinson, P., Ross, M. & Jaffe, H. W. 1971. Composition of the anthophyllite-gedrite series, comparisons of gedrite and hornblende and the anthophyllite-gedrite solvus. AM MINERAL 56, 1005–41.Google Scholar
Sangster, D. F. & Scott, S. D. 1976. Precambrian, strata-bound massive Cu-Zn-Pb sulphide ores of North America. In Wolf, K. H. (ed.) Handbook of Stratabound and Stratiform Ore Deposits 6, 129–222. Amsterdam: Elsevier.Google Scholar
Schermerhorn, L. T. G. 1978. Epigenetic magnesium metasomatism or syngenetic chloritite metamorphism at Falun and Orijärvi. TRANS INST MIN METALL 87, B162–7.Google Scholar
Smellie, J. A. T. 1974. Formation of atoll garnets from the aureole of the Ardara pluton, Co. Donegal, Ireland. MINERAL MAG 39, 878–88.CrossRefGoogle Scholar
Spear, F. S. 1980. The gedrite-anthophyllite solvus and the composition limits of orthoamphibole from the Post Pond Volcanics, Vermont. AM MINERAL 65, 1103–18.Google Scholar
Sturt, B. A. & Harris, A. L. 1961. The metamorphic history of the Loch Tummel area, Central Perthshire, Scotland. LIVERPOOL MANCHESTER GEOL J 2, 689–711.CrossRefGoogle Scholar
Thompson, A. B. 1976. Mineral reactions in pelitic rocks: II Calculation of some P-T-X (Fe-Mg) phase relations. AM J SCI 276, 425–54.CrossRefGoogle Scholar
Tracy, R. J., Robinson, P. & Thompson, A. B. 1976. Garnet composition and zoning in the determination of temperature and pressure of metamorphism, central Massachusetts. AM MINERAL 61, 762–75.Google Scholar
Treloar, P. J. 1981. Garnet-cordierite thermometry and barometry in the Cashel thermal aureole Connemara, Ireland. MINERAL MAG 44, 183–9.CrossRefGoogle Scholar
Treloar, P. J. & Putnis, A. 1982. Chemistry and microstructure of orthoamphiboles from cordierite-amphibole rocks at Outokumpu, North Karelia, Finland. MINERAL MAG (Deer, Howie and Zussman Volume—in press).CrossRefGoogle Scholar
Tuominen, H. V. & Mikkola, T. 1950. Metamorphic Mg-Fe enrichment in the Orijàrvi region as related to folding. BULL COMM GEOL FINL 150, 67–92.Google Scholar
Vähätalo, V. 1953. On the geology of the Outokumpu ore deposit in Finland. BULL COMM GEOL FINL 164, 1–98.Google Scholar
Vallance, T. G. 1967. Mafic rock alteration and isochemical development of some cordierite-anthophyllite rocks. J PETROL 3, 84–96.CrossRefGoogle Scholar
Väyrynen, H. 1939. On the geology and tectonics of the Outokumpu ore field and region. BULL COMM GEOL FINL 124, 1–91.Google Scholar
Vrána, S. 1975. Magnesian-aluminous rocks, the associated ore mineralization and the problem of magnesium-iron metasomatism. KRYSTALINIKUM 11, 101–14.Google Scholar
Yardley, B. W. D. 1981. A note on the composition and stability of Fe-staurolite. NEUES JAHRB MINERAL MONATSH, 127–32.Google Scholar
Zen, E-an 1973. Thermochemical parameters of minerals from oxygen-buffered hydrothermal equilibrium data: method and application to annite and almandine. CONTRIB MINERAL PETROL 39, 65–80.CrossRefGoogle Scholar