Contributions to Mineralogy and Petrology

, Volume 79, Issue 2, pp 187–200 | Cite as

Crystal growth and the formation of chemical zoning in garnets

  • Randall T. Cygan
  • Antonio C. Lasaga


A crystal growth model is developed which generalizes the Rayleigh fractionation process. The new growth model allows some insight into the interpretation of nonequilibrium behavior of minerals, primarily the chemical zoning profiles exhibited by metamorphic minerals. A nonlinear equilibrium term for exchange of constituents between a growing mineral and a reservoir is initially incorporated into the usual isothermal fractionation model. Criteria are established to decide when a simple distribution term is sufficient to describe the growth and exchange process. The model is then extended to allow for temperature changes during a cooling or heating event. Finally, an exact solution is obtained for the temperature dependent case incorporating a time dependent growth rate. The growth models are successfully used to obtain growth rates of 0.01 to 0.09 cm/million year and describe the magnesium and iron zoning profiles of garnets from Phillipston, Massachusetts. The generalized model confirms the development of zoning during the retrograde growth of garnet in the late stages of the Acadian orogeny.


Growth Model Orogeny Metamorphic Mineral Dependent Case Distribution Term 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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  1. Albarede F, Bottinga Y (1972) Kinetic disequilibrium in trace element partitioning between phenocryst and host lava. Geochim Cosmochim Acta 36:141–156Google Scholar
  2. Albee AL, Ray L (1970) Correction factors for electron-probe microanalysis of silicates, oxides, carbonates, phosphates and sulfates. Anal Chem 42:1408–1414Google Scholar
  3. Anderson DE, Buckley GR (1973) Zoning in garnets — diffusion models. Contrib Mineral Petrol 40:87–104Google Scholar
  4. Anderson DE, Buckley GR (1974) Modeling of diffusion controlled properties of silicates. In: Hofmann AW et al (eds) Geochemical transport and kinetics. Carnegie Inst Washington Publ, pp 31–52Google Scholar
  5. Anderson DE, Olimpio JC (1977) Progressive homogenization of metamorphic garnets, South Morar, Scotland: evidence for volume diffusion. Can Mineral 15:205–216Google Scholar
  6. Atherton MP (1968) The variation in garnet, biotite and chlorite composition in medium grade pelitic rocks from the Dalradian, Scotland, with particular reference to the zonation in garnet. Contrib Mineral Petrol 18:347–371Google Scholar
  7. Atherton MP (1976) Crystal growth models in metamorphic tectonites. Philos Trans R Soc London Ser A283:255–270Google Scholar
  8. Atherton MP, Edmunds WM (1966) An electron microprobe study of some zoned garnets from metamorphic rocks. Earth Planet Sci Lett 1:185–193Google Scholar
  9. Bence AE, Albee AL (1968) Empirical correction factors for the electron microanalysis of silicates and oxides. J Geol 76:382–403Google Scholar
  10. Birk D (1973) Chemical zoning in garnets of the Kashabowie group, Shebandowan, Ontario. Can Mineral 12:124–128Google Scholar
  11. Blackburn WH (1969) Zoned and unzoned garnets from the Grenville gneisses around Gananoque, Ontario. Can Mineral 9:691–698Google Scholar
  12. Brown EH (1969) Some zoned garnets from the greenschist facies. Am Mineral 54:1662–1677Google Scholar
  13. Cygan RT (1980) Crystal growth and the formation of chemical zoning in natural garnets. Pennsylvania State University MS thesis, 194 ppGoogle Scholar
  14. Cygan RT, Lasaga AC (1979) Formation of chemically zoned garnets by diffusion and crystal growth. EOS 60:741Google Scholar
  15. de Béthune P, Laduron D, Bacquet J (1975) Diffusion processes in resorbed garnets. Contrib Mineral Petrol 50:197–204Google Scholar
  16. Emiliani F, Venturelli G (1972) Sharp compositional zoning in an almandine garnet. Can Mineral 11:464–472Google Scholar
  17. Finlay CA, Kerr A (1979) Garnet growth in a metapelite from the Moinian rocks of Northern Sutherland, Scotland. Contrib Mineral Petrol 76:185–191Google Scholar
  18. Fisher GW (1977) Nonequilibrium thermodynamics in metamorphism. In: Fraser DG (ed) Thermodynamics in geology. Reidel, Dordrecht, pp 381–403Google Scholar
  19. Fisher GW (1978) Rate laws in metamorphism. Geochim Cosmochim Acta 42:1035–1050Google Scholar
  20. Gable DJ, Sims PK (1969) Geology and regional metamorphism of some high grade cordierite gneisses, Front Range, Colorado. Geol Soc Am Spec Pap 128:1–87Google Scholar
  21. Grant JA, Weiblen PW (1971) Retrograde zoning in garnet near the second sillimanite isograd. Am J Sci 270:281–296Google Scholar
  22. Harte B, Henley KJ (1966) Occurrence of compositionally zoned almanditic garnets in regionally metamorphosed rocks. Nature 210:689–692Google Scholar
  23. Hess PC (1971) Prograde and retrograde equilibria in garnet-cordierite gneisses in south-central Massachusetts. Contrib Mineral Petrol 30:177–195Google Scholar
  24. Hollister LS (1966) Garnet zoning: an investigation based on the Rayleigh fractionation model. Science 154:1647–1651Google Scholar
  25. Hollister LS (1969) Contact metamorphism in the Kwoiek area of British Columbia: an end member of the metamorphic process. Geol Soc Am Bull 80:2465–2494Google Scholar
  26. Jackson KA (1967) Current concepts in crystal growth from the melt. In: Reiss H (ed) Progress in solid state chemistry, vol 4. Pergamon Press, New York, pp 53–80Google Scholar
  27. Kretz R (1973) Kinetics of the crystallization of garnet at two localities near Yellowknife. Can Mineral 12:1–20Google Scholar
  28. Lasaga AC (1979) Multicomponent exchange and diffusion in silicates. Geochim Cosmochim Acta 43:455–469Google Scholar
  29. Lasaga AC, Richardson SM, Holland HD (1977) The mathematics of cation diffusion and exchange between silicate minerals during retrograde metamorphism. In: Saxena SK, Bhattacharji S (eds) Energetics of geological processes. Springer, New York, pp 353–388Google Scholar
  30. Linthout K, Westra L (1968) Compositional zoning in almandine-rich garnets and its relation to the metamorphic history of their host rocks. Proc K Ned Akad Wet Ser B 71:297–312Google Scholar
  31. Loomis TP (1975) Reaction zoning of garnet. Contrib Mineral Petrol 52:285–305Google Scholar
  32. McIntire WL (1963) Trace element partition coefficients —a review of theory and application to geology. Geochim Cosmochim Acta 27:1209–1264Google Scholar
  33. Miyashiro A (1953) Calcium-poor garnet in relation to metamorphism. Geochim Cosmochim Acta 4:179–208Google Scholar
  34. Miyashiro A, Shido F (1973) Progressive compositional change of garnet in metapelite. Lithos 6:13–20Google Scholar
  35. Müller G, Schneider A (1971) Chemistry and genesis of garnets in metamorphic rocks. Geochim Cosmochim Acta 31:178–200Google Scholar
  36. Neumann H, Mead J, Vitaliano CJ (1954) Trace element variation during fractional crystallization as calculated from the distribution law. Geochim Cosmochim Acta 6:90–99Google Scholar
  37. Nielsen AE (1964) Kinetics of precipitation. Pergamon Press, New York, 151 ppGoogle Scholar
  38. Rayleigh L (1902) On the distillation of binary mixtures. Philos Mag 4:521–537Google Scholar
  39. Richardson SM (1982) The assemblage garnet+cordierite+biotite+sillimanite in a metavolcanic rock at Phillipston, Massachusetts. Contrib Mineral Petrol (in press)Google Scholar
  40. Thompson AB (1974) Calculation of muscovite-paragonite-alkali feldspar phase relations. Contrib Mineral Petrol 44:173–194Google Scholar
  41. Thompson AB (1976) Mineral reactions in pelitic rocks: I. prediction of P-T-X(Fe-Mg) phase relations. Am J Sci 276:401–424Google Scholar
  42. Thompson AB, Tracy RJ, Lyttle PT, Thompson JB (1977) Prograde reaction histories deduced from compositional zonation and mineral inclusions in garnet from the Gassetts schist, Vermont. Am J Sci 277:1152–1167Google Scholar
  43. Thompson JB, Norton SA (1968) Paleozoic regional metamorphism in New England and adjacent areas. In: Zen E et al (eds) Studies of Appalachian geology, Northern and Maritime. Wiley, New York, pp 319–328Google Scholar
  44. Tracy RJ, Robinson P, Thompson AB (1976) Garnet composition and zoning in the determination of temperature and pressure of metamorphism, central Massachusetts. Am Mineral 61:762–775Google Scholar
  45. Woodsworth GJ (1977) Homogenization of zoned garnets from schists. Can Mineral 15:230–242Google Scholar
  46. Yardley BWD (1977) An empirical study of diffusion in garnet. Am Mineral 62:793–800Google Scholar

Copyright information

© Springer-Verlag 1982

Authors and Affiliations

  • Randall T. Cygan
    • 1
  • Antonio C. Lasaga
    • 1
  1. 1.Department of GeosciencesThe Pennsylvania State UniversityUniversity ParkUSA

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