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Garnet-cordierite-biotite equilibria in the Steinach aureole, Bavaria

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Abstract

Three garnet-biotite pairs and eleven garnet-cordierite-biotite triplets from the Steinach aureole (Oberpfalz, North-East Bavaria) were analyzed using an electron probe microanalyzer.

The regional metamorphic muscovite-biotite schists contain garnets strongly zoned with Mn-Ca-rich centers and Fe-rich edges, the average composition being almandine 67 — spessartine 4 — pyrope 4 — grossular (+andradite) 25.

The first contact garnet that is formed in mica schists of the outermost part of the aureole is small, virtually unzoned, and has an average composition of almandine 52 — spessartine 37 — pyrope 8 — grossular (+andradite) 3. With increasing metamorphic grade, there is a consistent trend to form garnets richer in Fe ending up with a composition almandine 84.5 — spessartine 5.5 — pyrope 7.5 — grossular (+andradite) 2.5. This trend is accompanied by a general increase in grain size and modal amount of garnet. Associated cordierites and biotites also become richer in Fe with increasing grade. While the garnets in the highest grade sillimanite hornfelses are poorly zoned, the transitional andalusite-sillimanite hornfelses contain garnets with distinct but variable zonation profiles.

These facts can possibly be explained by the time-temperature relationships in the thermal aureole. In a phase diagram such as the Al′-Fe-Mg-Mn tetrahedron, the limiting mineral compositions of a four-phase volume or a three-phase triangle are fixed by T and P (the latter remaining effectively constant within a thermal aureole). Thus, in garnet-cordierite-biotite assemblages, garnet zonation should be controlled by temperature variation rather than by a non-equilibrium depletion process. Taking into account the experimental data of Dahl (1968), a zoned garnet from a transitional andalusite-sillimanite hornfels would reflect a temperature increase of about 40° C during its growth. A hypothetical P-X diagram is proposed to show semi-quantitatively the compositional variation of garnet-cordierite pairs with varying pressures (T constant).

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References

  • Althaus, E.: The triple point andalusite-sillimanite-kyanite. Contr. Mineral. and Petrol. 16, 29–44 (1967).

    Google Scholar 

  • Atherton, M. P.: The variation in garnet, biotite, and chlorite composition in medium grade pelitic rocks from the Dalradian, Scotland, with particular reference to the zonation of garnet. Contr. Mineral. and Petrol. 18, 347–371 (1968).

    Google Scholar 

  • —, Edmunds, W. M.: An electron microprobe study of some zoned garnets from metamorphic rocks. Earth and Planet. Sci. Letters 1, 185–193 (1966).

    Google Scholar 

  • Banno, S.: Notes on rock forming minerals (34), zonal structure of pyralspite in Sanbagawa Schists in the Bessi area, Sikoku. J. Geol. Soc. Japan 71, 185–188 (1965).

    Google Scholar 

  • Barker, F.: Cordierite-garnet gneiss and associated microcline-rich pegmatite at Sturbridge, Massachusetts and Union, Connecticut. Am. Mineralogist 47, 907–918 (1962).

    Google Scholar 

  • —: Sapphirine-bearing rocks, Val Codera, Italy. Am. Mineralogist 49, 146–152 (1964).

    Google Scholar 

  • Best, M. G., Weiss, L. E.: Mineralogical relations in some pelitic hornfelses in the southern Sierra Nevada, California. Am. Mineralogist 49, 1240–1266 (1964).

    Google Scholar 

  • Béthune, P. de, Laduron, D., Martin, H., Theunissen, K.: Grenats zonés de la zone du Mont Rose (Valle Anzasca, Prov. de Novara, Italie). Schweiz. Mineral. Petrol. Mitt. 48, 437–454 (1968).

    Google Scholar 

  • Blackburn, W. H.: Zoned and unzoned garnets from the Grenville gneisses around Gananoque, Ontario. Can. Mineralogist 9, 691–698 (1969).

    Google Scholar 

  • Brown, E. H.: Some zoned garnets from the greenschist facies. Am. Mineralogist 54, 1662–1677 (1969).

    Google Scholar 

  • Buddington, A. F., Lindsley, D. H.: Iron-titanium oxide minerals and synthetic equivalents. J. Petrol. 5, 310–357 (1964).

    Google Scholar 

  • Burns, L. K.: Unpublished Ph. D. thesis, Department of Geology and Geophysics, University of California, Berkeley (1969).

  • Butler, B. C. M.: Chemical study of minerals from the Moine schists of the Ardnamurchan area, Argyllshire, Scotland. J. Petrol. 8, 233–267 (1967).

    Google Scholar 

  • Chinner, G. A.: Pelitic gneisses with varying ferrous/ferric ratios from Glen Clova, Angus, Scotland. J. Petrol. 1, 178–217 (1960).

    Google Scholar 

  • —: Almandine in thermal aureoles. J. Petrol. 3, 316–340 (1962).

    Google Scholar 

  • Dahl, O.: Hydrothermal studies of garnet-mica equilibria in the system 3(FeO, MnO)-2Al2O3-12SiO2-K2O-H2O. Geol. Fören. Förh. 90, 331–348 (1968).

    Google Scholar 

  • Drake, J. C.: The composition of almandine and coexisting minerals in the mica schists of the Errol quadrangle, New Hampshire-Maine. Harvard Ph. D. thesis (1968), Abstract GSA-Meeting, Mexico (1968).

  • Eskola, P.: On the petrology of the Orijärvi region in southwestern Finland. Bull. Comm. Geol. Finlande 40 (1914).

  • - On the relations between the chemical and mineralogical composition in the metamorphic rocks of the Orijärvi region. Bull. Comm. Geol. Finlande 44 (1915).

  • Evans, B. W.: Application of a reaction rate method to the breakdown of muscovite and muscovite plus quartz. Am. J. Sci. 263, 647–667 (1965).

    Google Scholar 

  • Fischer, G.: Über das Grundgebirge der Bayerischen Ostmark. Die Gneise nördlich des Pfahls. Jahrb. preuss. geol. Landesanstalt (Berlin) 59, 289–352 (1938).

    Google Scholar 

  • Gorbatschev, R.: Distribution of elements between cordierite, biotite, and garnet. Neues Jahrb. Mineral. Abhand. 110, 57–80 (1968).

    Google Scholar 

  • Harte, B., Henley, K. J.: Occurrence of compositionally zoned almanditic garnet in regionally metamorphosed rocks. Nature 210, 689–692 (1966).

    Google Scholar 

  • Heald, M. T.: Structure and petrology of the Lovewell mountain quadrangle, New Hampshire. Geol. Soc. Am. Bull. 61, 43–89 (1950).

    Google Scholar 

  • Hensen, B. J., Green, D. H.: Experimental data on coexisting cordierite and garnet under high grade metamorphic conditions. Phys. Earth Planet. Int. 3, 431–440 (1970).

    Google Scholar 

  • Hess, P. C.: The metamorphic paragenesis of cordierite in pelitic rocks. Contr. Mineral. and Petrol. 24, 191–207 (1969).

    Google Scholar 

  • Hietanen, A.: Kyanite, andalusite, and sillimanite in schists in Boehls Butte quadrangle, Idaho. Am. Mineralogist 41, 1–27 (1956).

    Google Scholar 

  • Hirschberg, A., Winkler, H. G. F.: Stabilitätsbeziehungen zwischen Chlorit, Cordierit und Almandin bei der Metamorphose. Contr. Mineral. and Petrol. 18, 17–42 (1968).

    Google Scholar 

  • Hollister, L. S.: Garnet zoning: an interpretation based on the Rayleigh fractionation model. Science 154, 1647–1651 (1966).

    Google Scholar 

  • —: Contact metamorphism in the Kwoiek area of British Columbia: an end member of the metamorphic process. Geol. Soc. Am. Bull. 80, 2465–2494 (1969).

    Google Scholar 

  • Hsu, L. C.: Selected phase relationships in the system Al-Mn-Fe-Si-O-H: A model for garnet equilibria. J. Petrol. 9, 40–83 (1968).

    Google Scholar 

  • —, Burnham, C. W.: Phase relationships in the system Fe3Al2Si3O12-Mg3Al2Si3O12-H2O at 2.0 kilobars. Geol. Soc. Am. Bull. 80, 2393–2408 (1969).

    Google Scholar 

  • Jaeger, J. C.: The temperatures in the neighborhood of a cooling intrusive sheet. Am. J. Sci. 255, 306–318 (1957).

    Google Scholar 

  • —: Temperatures outside a cooling intrusive sheet. Am. J. Sci. 257, 44–54 (1959).

    Google Scholar 

  • Knorring, O. von, Kennedy, W. Q.: The mineral paragenesis and metamorphic status of garnet-hornblende-pyroxene-scapolite gneiss from Ghana (Gold Coast). Mineral. Mag. 31, 846–859 (1958).

    Google Scholar 

  • Kretz, R.: Chemical study of garnet, biotite, and hornblende from gneisses of south-western Quebec, with emphasis on distribution of elements in coexisting minerals. J. Geol. 67, 371–402 (1959).

    Google Scholar 

  • Lambert, R. St. J.: The mineralogy and metamorphism of the Moine schists of the Morar and Knoydart districts of Inverness-shire. Trans. Roy. Soc. Edinburgh 63, 553–588 (1959).

    Google Scholar 

  • Matthes, S.: Ergebnisse zur Granatsynthese und ihre Beziehungen zur Granatbildung innerhalb der Pyralspitgruppe. Geochim. Cosmochim. Acta 23, 233–294 (1961).

    Google Scholar 

  • Miyashiro, A.: Cordierite-indialite relations. Am. J. Sci. 255, 43–62 (1957).

    Google Scholar 

  • Okrusch, M.: Die Gneishornfelse um Steinach in der Oberpfalz — Eine phasenpetrologische Analyse. Contr. Mineral. and Petrol. 22, 32–72 (1969).

    Google Scholar 

  • —, Evans, B. W.: Minor element relationships in coexisting andalusite and sillimanite. Lithos 3, 261–268 (1970).

    Google Scholar 

  • Pabst, A.: Garnets from the vesicles in rhyolite near Ely, Nevada. Am. Mineralogist 23, 233–245 (1938).

    Google Scholar 

  • Reinhardt, E. W.: Phase relations in cordierite-bearing gneisses from the Gananoque area, Ontario. Can. J. Earth Sci. 5, 455–482 (1968).

    Google Scholar 

  • Richardson, S. W.: Staurolite stability in a part of the system Fe-Al-Si-O-H. J. Petrol. 9, 467–488 (1968).

    Google Scholar 

  • —, Gilbert, M. C., Bell, P. M.: Experimental determination of kyanite-andalusite and andalusite-sillimanite equilibria: the aluminium silicate triple point. Am. J. Sci. 267, 259–272 (1969).

    Google Scholar 

  • Rimšaite, J. Y. H.: Rock forming micas. Geol. Surv. Canada Paper 64, 82–86 (1964).

    Google Scholar 

  • Saxena, S. K., Hollander, N. B.: Distribution of iron and magnesium in coexisting biotite, garnet, and cordierite. Am. J. Sci. 267, 210–216 (1969).

    Google Scholar 

  • Schreyer, W.: Zur Stabilität des Ferrocordierits. Contr. Mineral. and Petrol. 11, 297–322 (1965).

    Google Scholar 

  • —: Metamorpher Übergang Saxothuriugikum-Moldanubikum östlich Tirschenreuth/Obpf., nachgewiesen durch phasenpetrologische Analyse. Geol. Rundschau 55, 481–509 (1966).

    Google Scholar 

  • Schreyer, W.: A reconnaissance study of the system MgO-Al2O3-SiO2-H2O at pressures between 10 and 25 kb. Carnegie Inst. Washington Yearbook 66, 380–392 (1968).

    Google Scholar 

  • —, Seifert, F.: Compatibility relations of the aluminium silicates in the systems MgO-Al2O3-SiO2-H2O and K2O-MgO-Al2O3-SiO2-H2O at high pressures. Am. J. Sci. 267, 371–388 (1969).

    Google Scholar 

  • —, Yoder, H. S.: Petrographic guides to the experimental petrology of cordierite. Carnegie Inst. Washington Yearbook 60, 147–152 (1961).

    Google Scholar 

  • Schröcke, H.: Petrotektonische Untersuchung des Cordieritgneisgebietes um Bodenmais im Bayr. Wald und der eingelagerten Kieslagerstätten. Heidelberger Beitr. Mineral. Petrogr. 4, 464–503 (1955).

    Google Scholar 

  • Sidorenko, E. F.: Ferro-magnesian minerals from metamorphic rocks of the Dnjestr district. Mineral. Sbornik Geol. Soc. Lvov 15, 189–197 (1961) [Russ., cit. Miner. Abstr. 18, 41].

    Google Scholar 

  • Speidel, D. H.: Effect of magnesium on the iron-titanium oxides. Am. J. Sci. 268, 341–353 (1970).

    Google Scholar 

  • Stewart, F. H.: Chemical data on a silica-poor argillaceous hornfels and its constituent minerals. Mineral. Mag. 26, 260–266 (1942).

    Google Scholar 

  • Turner, F. J.: Metamorphic petrology—mineralogical and field aspects. New York-San Francisco-St. Louis-London-Toronto-Sydney: McGraw-Hill Book Comp. 1968.

    Google Scholar 

  • Voll, G.: Stoff, Bau und Alter in der Grenzzone Moldanubikum/Saxothuringikum in Bayern unter besonderer Berücksichtigung gabbroider, amphibolitischer und kalksilikatführender Gesteine. Geol. Jahrb. Beih. 42, 1–382 (1960).

    Google Scholar 

  • Wimmenauer, W.: Cordieritführende Gesteine im Grundgebirge des Schauinslandgebietes. Neues Jahrb. Mineral. Abhand. 80, 375–436 (1950).

    Google Scholar 

  • Wynne-Edwards, H. R., Hay, P. W.: Coexisting cordierite and garnet in regionally metamorphosed rocks from the Westport area, Ontario, Canada. Can. Mineralogist 7, 453–478 (1963).

    Google Scholar 

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  1. Mineralogisch-Petrographisches Institut der Universität zu Köln, Cologne, Germany

    Martin Okrusch

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Okrusch, M. Garnet-cordierite-biotite equilibria in the Steinach aureole, Bavaria. Contr. Mineral. and Petrol. 32, 1–23 (1971). https://doi.org/10.1007/BF00372230

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