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Mineralogical data on a multiple intrusion in the Rustenburg Layered Suite of the Bushveld Complex

Published online by Cambridge University Press:  05 July 2018

G. Davies  and
R. G. Cawtnorn
G. Davies
Affiliation:
Nuclear Physics Research Unit, University of the Witwatersrand, Jan Smuts Avenue, Johannesburg 2001, South Africa
R. G. Cawtnorn
Affiliation:
Department of Geology, University of the Witwatersrand, Jan Smuts Avenue, Johannesburg 2001, South Africa
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Abstract

Mineralogical and chemical data are presented on an intrusion of a hypersthene gabbro body into coarse-grained noritic cumulates of the critical zone, which occurs at the margin of the Rustenburg Layered Suite of the Bushveld Complex. Two types of contact relations are found between the above two rock suites: (1) a clearly cross-cutting contact is observed on the southern margin of the hypersthene gabbro body close to the interface between the layered suite and the floor rocks; (2) a diffuse heterogeneous contact is found on the north-western limb of the body which is further into the complex. Field observations and chemical data suggest that, at the time of the hypersthene gabbro injection, the surrounding cumulates were above ambient temperatures. The difference in the contacts described above is probably related to the prevailing temperature gradient at the time of emplacement. The cumulate rocks further into the complex were at a higher temperature than those closer to the margin.

Trace element chemistry and phase relations in the basalt tetrahedron indicate that the hypersthene gabbro is genetically unrelated to the cumulate rocks which it intrudes. The body probably represents an offshoot of the magma from which the upper zone of the Rustenburg Layered Suite crystallized.

Type
Research Article
Information
Mineralogical Magazine , Volume 48 , Issue 349 , December 1984 , pp. 469 - 480
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1984

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Footnotes

*

Present address: NBRI, CSIR, PO Box 395, Pretoria 0001, South Africa.

References

Albee, A. L., and Ray, L. (1970) Analyt. Chem. 42, 1408–14.CrossRefGoogle Scholar
Biggar, G. M. (1974) Contrib. Mineral. Petrol. 46, 159–67.CrossRefGoogle Scholar
Cameron, E. N. (1970) Geol. Soc. S.Afr. Spec. Publ. 1, 46–58.Google Scholar
Cameron, E. N. (1978) J. Petrol. 19, 437–62.CrossRefGoogle Scholar
Cawthorn, R. G., and Davies, G. (1983) Contrib. Mineral. Petrol. 83, 128–135.CrossRefGoogle Scholar
Cawthorn, R. G., Davies, G., Clubley-Armstrong, A., and McCarthy, T. S. (1981) Lithos. 14, 1–15.CrossRefGoogle Scholar
Coertze, F. J. (1968) Trans. Geol. Soc. S.Afr. 61, 387–92.Google Scholar
Coertze, F. J. (1974) Geol. Soc. S.Afr., Spec. Publ. 1, 5–22.Google Scholar
Cousins, C. A. (1959) Trans. Geol. Soc. S.Afr. 62, 179–201.Google Scholar
Cousins, C. A. and Feringa, G. (1964) In The Geology of Some Ore Deposits of Southern Africa (Haughton, S. H., ed.) Geol. Soc. of S. Afr., Johannesburg, 183–202.Google Scholar
Daly, R. A. (1928) Geol. Soc. Am. Bull. 39, 703–68.CrossRefGoogle Scholar
Davies, G., Cawthorn, R. G., Barton, J. M. Jr., and Morton, M. (1980) Nature. 287, 33–5.CrossRefGoogle Scholar
Dunham, A. C., and Wadsworth, M. J. (1978) Mineral. Mag. 42, 347–56.CrossRefGoogle Scholar
Gijbels, R. H., Millard, H. T., Desborough, G. A., and Bartel, A. J. (1974) Geochim. Cosmochim. Acta. 38, 319–37.CrossRefGoogle Scholar
Hall, A. L. (1932) Geol. Surv. S.Afr. Mem. 28.Google Scholar
Hamilton, J. (1977) J. Petrol. 18, 24–52.CrossRefGoogle Scholar
Hess, H. H. (1960) Geol. Soc. Am. Mem. 80.Google Scholar
Irvine, T. (1970) Geol. Soc. S.Afr., Spec. Publ. 1, 441–76.Google Scholar
Irvine, T. (1977) Geology. 5, 273–77.2.0.CO;2>CrossRef2.0.CO;2>Google Scholar
Kushiro, I. (1969) Am. J. Sci. 261A., 269–94.Google Scholar
Lombard, B. V. (1934) Trans. Geol. Soc. S.Afr. 37, 5–52.Google Scholar
McCarthy, T. S., and Cawthorn, R. G. (1980) J. Petrol. 21, 245–64.CrossRefGoogle Scholar
Markgraaff, J. (1976) Trans. Geol. Soc. S.Afr. 79, 217–24.Google Scholar
Medaris, L. G. Jr. (1969) Am. J. Sci. 267, 945–68.CrossRefGoogle Scholar
Molyneux, T. G. (1974) Trans. Geol. Soc. S.Afr. 77, 32938.Google Scholar
Nel, H. J. (1940) Trans. Geol. Soc. S.Afr. 43, 37–68.Google Scholar
Reuning, E. (1928) Neues Jahrb. Beil. Bd. 57A, 631–64.Google Scholar
Roeder, P. L., and Emslie, R. F. (1970) Contrib. Mineral. Petrol. 29, 275–89.CrossRefGoogle Scholar
Schwellnus, J. S. I. (1956) The basal portion of the Bush- veld Igneous Complex and the adjoining metamorphosed sediments in the north east Transvaal. D.Sc. thesis, Pretoria University. South Africa.Google Scholar
Sharpe, M. R. (1980) Inst, for Geol. Res. on the Bushveld Complex, Univ. of Pretoria, Report. 20, 57.pp.Google Scholar
Sharpe, M. R. (1981) J. Geol. Soc. London. 138, 307–29.CrossRefGoogle Scholar
Tilley, C. E., Yoder, H. J. Jr., and Schairer, J. F. (1967) Carnegie Inst. Washington Yearb. 66, 450–7.Google Scholar
Truter, F. L. (1955) C.C.T.A. South reg. Comm. Geol. 1, 77–87.Google Scholar
von Gruenewaldt, G. (1970) Geol. Soc. S.Afr. Spec. Pub. 1, 67–73.Google Scholar
von Gruenewaldt, G. (1973) Trans. Geol. Soc. S.Afr. 76, 53–61.Google Scholar
Wager, L. R., and Brown, G. M. (1968) Layered Igneous Rocks, Oliver and Boyd, London.Google Scholar
Willemse, J. (1959) Proc. Geol. Soc. S.Afr. 62, xxi–lxxx.Google Scholar
Willemse, J. (1969) Econ. Geol. Mono. 4, 1–22.Google Scholar
Williams, R. J., and Eugster, H. P. (1969) Geol. Soc. Am. Ann. Meeting Abstr. 237.Google Scholar