Hostname: page-component-586b7cd67f-g8jcs Total loading time: 0 Render date: 2024-11-22T05:43:40.536Z Has data issue: false hasContentIssue false
  • English
  • Français

Distinct cooling histories of troctolites from the Freetown layered gabbro

Published online by Cambridge University Press:  05 July 2018

John F. W. Bowles
John F. W. Bowles*
Affiliation:
Department of Geology, University College, London, WC1E 6BT
Get access Rights & Permissions [Opens in a new window]

Summary

The iron-titanium oxide minerals of three troctolites from the Freetown layered gabbro have been analysed using an electron microprobe. Comparisons of the analyses of the iron-titanium minerals with the data of Buddington and Lindsley (1964) provide temperature and oxygen fugacity information relating to particular magnetite-ilmenite grains. Magnetite-ilmenite grains occurring in different silicate environments within any one single troctolite rock have equilibrated at differing times in the cooling history of that rock and this enables part of that history to be established. The partial cooling histories established for the three specimens can be clearly distinguished, and are strongly influenced by the appropriate buffer reactions.

Type
Research Article
Information
Mineralogical Magazine , Volume 40 , Issue 315 , September 1976 , pp. 703 - 714
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1976

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.)

Footnotes

1

Present address: Institute of Geological Sciences, 64/78 Gray's Inn Road, London, WCIX 8NG.

References

Anderson, (J. T.), 1968. Journ. Geol. 76, 528-47 [M.A. 72-2835].CrossRefGoogle Scholar
Bowles, (J. F. W.), in press. Min. Mag. Google Scholar
Bowles, (J. F. W.), 1975. Rep. Inst. Geol. Sci. no. 75/9.Google Scholar
Buddington, (A. F.), 1963. Indian Geophys. Union, M.S. Krishnan Vol., 233-48.Google Scholar
Buddington, (A. F.), and Lindsley, (D. H.), 1964. Journ. Petrology, 5, 310-357 [M.A. 17-278].CrossRefGoogle Scholar
Carmichael, (I. S. E.), 1967. Contr. Min. Petr. 14, 36-64.CrossRefGoogle Scholar
Czamanske, (G. K.) and Mihálik, (P.), 1972. Journ. Petrology, 13, 493-509.[M.A. 73-1906].CrossRefGoogle Scholar
Dasgupta, (H. C.), 1970. Journ. Geol. 78, 243-9.[M.A. 73-1653].CrossRefGoogle Scholar
Drake, (M. J.), 1975. Geochimica Acta, 39, 55-64.CrossRefGoogle Scholar
Duchesne, (J. C.), 1972. Journ. Petrology, 13, 57-81.[M.A. 72-2274].CrossRefGoogle Scholar
Elsdon, (R.), 1971. Min. Mag. 38, 49-57.[M.A. 71-1307].CrossRefGoogle Scholar
Elsdon, (R.), 1972. Ibid. 38, 946-956 [M.A. 73-738].CrossRefGoogle Scholar
Gasparrini, (E.), and Naldrett, (A. J.), 1972. Econ. Geol. 67, 605-21.[M.A. 73-4045].CrossRefGoogle Scholar
Mason, (P. K.), Frost, (M. T.), and Reed, (S. J. B.), 1969. N.P.L. (I.M.S.) Report No. 2.Google Scholar
Verhoogen, (J.), 1962. Journ. Geol. 70, 168-81 [M.A. 16-72].CrossRefGoogle Scholar
Wager, (L. R.) and Mitchell, (R. L.), 1951. Geochimica Acta, 1, 129-208 [M.A. 11-495].CrossRefGoogle Scholar
Wells, (M. K.), 1962. Geol. Surv. Dept. Sierra Leone, Short Paper No. 9. (Bull. Overseas Geol. Min. Res., Suppl. No. 4) [M.A. 16-305].Google Scholar