Letter | Published:

Order-modulated structures and the thermodynamics of cordierite reactions

Naturevolume 287pages128131 (1980) | Download Citation



The determination of palaeo pressures and temperatures (P, T) in metamorphic belts is of fundamental importance to our understanding of large-scale physical processes in the Earth. Such determinations are made by comparing observed mineral assemblages with experimental data on their P, T stability fields1, thus assuming that the experiments are an adequate model for the natural reaction. The characterization of the structural state of natural and experimental materials is particularly important in this context. This note demonstrates the effect of the state of cation order on the P, T slopes of metamorphic reactions involving cordierite, (Mg, Fe)2Al4Si5O18, an indicator phase in metamorphism. Particular emphasis will be placed on the mechanism of Al, Si ordering in cordierite in so far as it relates to the characterization of the degree of cation order and hence the configurational entropy contribution to the thermodynamics of cordierite reactions.

Access optionsAccess options

Rent or Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.


  1. 1

    Richardson, S. W. Fortschr. Miner. 47, 65–76 (1970).

  2. 2

    Schreyer, W. & Schairer, J. F. J. Petrol. 2, 294–406 (1961).

  3. 3

    Putnis, A. Contr. Miner. Petrol. (in the press).

  4. 4

    Meagher, E. P. & Gibbs, G. V. Can Miner. 15, 43–49 (1977).

  5. 5

    Putnis, A. Phys. Chem. Miner. (submitted).

  6. 6

    Miyashiro, A. Am. J. Sci. 255, 43–62 (1957).

  7. 7

    Schreyer, W. Neues Jb. Miner. Abh. 105, 211–244 (1966).

  8. 8

    Stout, J. H. Am. Miner. 60, 229–234 (1975).

  9. 9

    Schreyer, W., Gordillo, C. E. & Werding, G. Cont. Miner. Petrol. 70, 421–428 (1979).

  10. 10

    Sellkregg, K. R. & Bloss, F. D. Geol. Soc. Am. Abstr. 11, 513 (1979).

  11. 11

    Navrotsky, A. & Kleppa, O. J. J. Am. ceram. Soc. 56, 198–199 (1973).

  12. 12

    Newton, R. C., Charlu, T. V. & Kleppa, O. J. Contr. Miner. Petrol. 44, 295–311 (1974).

  13. 13

    Newton, R. C. & Wood, B. J. Contr. Miner. Petrol. 68, 391–405 (1979).

  14. 14

    Newton, R. C. J. Geol. 80, 398–420 (1972).

  15. 15

    Merlino, S. Contr. Miner. Petrol. 41, 23–29 (1973).

  16. 16

    Higgins, J. B. thesis, Virginia Polytechnic Institute, Blacksburg (1978).

  17. 17

    Charlu, T. V., Newton, R. C. & Kleppa, O. J. Geochim. cosmochim. Acta 39, 1487–1498 (1975).

Download references

Author information


  1. Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge, CB2 3EQ, UK

    • A. Putnis


  1. Search for A. Putnis in:

About this article

Publication history



Issue Date



Further reading


By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.