Contributions to Mineralogy and Petrology

, Volume 20, Issue 2, pp 115–134 | Cite as

Petrology of the Nandewar Volcano, N.S.W., Australia

  • M. J. Abbott
Article

Abstract

The Nandewar Mountains, N.S.W., Australia, are the remains of a Miocene continental alkaline volcano whose products range from olivine basalts to comendites and alkali rhyolites. Intermediate hawaiites, mugearites and benmoreites predominate in the shield, in which olivine basalts are rare, and the trachytic rocks form many intrusions into the shield. The Nandewar alkaline series shows extreme fractionation of a relatively differentiated alkali olivine basalt magma, saturated with silica, to yield extremely oversaturated peralkaline comendites and peraluminous alkali rhyolites. The nature of the ferromagnesian phases forming was controlled by low oxygen fugacities. Throughout the series clinopyroxenes range from diopsidic augite, through sodic ferrohedenbergites to hedenbergite-acmite solid solutions. Riebeckite-arfvedsonite solid solutions appear in the trachytes and comendites, and aenigmatite appears in some of the peralkaline rocks. The feldspars in the series fractionate from calcic labradorite through potash oligoclase and calcic anothoclase towards the minimum melting alkali feldspar composition, Ab65Or35. The compositions of the alkali rhyolites approach the minimum in the system SiO2-KAlSi3O8-NaAlSi3O8. All the mineralogical and chemical evidence points to the development of the Nandewar series by the processes of extreme crystallization differentiation of an alkali olivine basalt parent magma. No significant contamination occurred, xenoliths and xenocrysts are absent, and volatile transfer and metasomatism played a minor role.

Keywords

Oxygen Fugacity Olivine Basalt Crystallization Differentiation Alkali Olivine Basalt Basalt Parent 
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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References

  1. Abbott, M. J.: K and Rb in a continental alkaline igneous rock suite. Geochim. et Cosmochim. Acta 31, 1035–1041 (1967a).Google Scholar
  2. —: Aenigmatite from the groundmass of a peralkaline trachyte. Am. Mineralogist 52, 1895–1901 (1967b).Google Scholar
  3. Aoki, K. I.: Clinopyroxenes from alkaline rocks of Japan. Am. Mineralogist 49, 1199–1223 (1964).Google Scholar
  4. Bailey, D. K., and J. F. Schairer: Feldspar-liquid equilibria in peralkaline liquids — the orthoclase effect. Am. J. Sci. 262, 1198–1206 (1964).Google Scholar
  5. — —: The system Na2O-Al2O3-Fe2O3-SiO2 at 1 atmosphere, and the petrogenesis of alkaline rocks. J. Petrology 7, 114–170 (1966).Google Scholar
  6. Bowen, N. L.: Phase equilibria bearing on the origin and differentiation of alkaline rocks. Am. J. Sci. 243A, Daly vol., 75–89 (1945).Google Scholar
  7. Buddington, A. F., and D. H. Lindsley: Iron-titanium oxide minerals and synthetic equivalents. J. Petrology 5, 310–357 (1964).Google Scholar
  8. Carmichael, I. S. E.: The feldspar phenocrysts of some Tertiary acid glasses. Mineral. Mag. 32, 587–608 (1960).Google Scholar
  9. —: Pantelleritic liquids and their phenocrysts. Mineral. Mag. 33, 86–113 (1962).Google Scholar
  10. —: The crystallization of feldspar in volcanic acid liquids. Quart. J. Geol. Soc. London 119, 95–131 (1963).Google Scholar
  11. —: Natural liquids and the phonolitic minimum. Geol. J. 4, 55–60 (1964).Google Scholar
  12. Chayes, F., and E. G. Zies: Sanidine phenocrysts in some peralkaline volcanic rocks. Ann. Rept. Gephys. Lab. Yearbook 61, 112–118 (1962).Google Scholar
  13. Deer, W. A., R. A. Howie, and J. Zussman: Rock forming minerals, vol. 2, Chain silicates. London: Longmans 1963.Google Scholar
  14. Edwards, A. B.: Three olivine basalt—trachyte provinces and some theories of petrogenesis. Proc. Roy. Soc. Victoria 48, 13–26 (1935).Google Scholar
  15. —: The tertiary volcanic rocks of Central Victoria. Quart. J. Geol. Soc. London 94, 243–320 (1938a).Google Scholar
  16. —: Petrology of the tertiary older volcanic rocks of Victoria. Proc. Roy. Soc. Victoria 51, 73–98 (1938b).Google Scholar
  17. Ernst, W. G.: Synthesis, stability relations, and occurrence of riebeckite and riebeckitearfvedsonite solid solutions. J. Geol. 70, 689–736 (1962).Google Scholar
  18. Jensen, H. I.: Geology of the volcanic area of the East Moreton and Wide Bay districts of Queensland. Proc. Linnean Soc. N.S.Wales 31, 73–173 (1906).Google Scholar
  19. —: The geology of the Warrumbungle Mountains. Proc. Linnean Soc. N. S. Wales 32, 557–626 (1907a).Google Scholar
  20. —: The geology of the Nandewar Mountains. Proc. Linnean Soc. N. S. Wales 32, 842–914 (1907b).Google Scholar
  21. Joplin, G. A.: A petrography of Australian igneous rocks. Sydney: Angus & Robertson 1964.Google Scholar
  22. LeMaitre, R. W.: Petrology of volcanic rocks, Gough Island, South Atlantic. Geol. Soc. Am. Bull. 73, 1309–1340 (1962).Google Scholar
  23. Lindsley, D. H.: Accessory minerals. Investigations in the system FeO-Fe2O3-TiO2. Ann. Rept. Geophys. Lab. Yearbook 61, 100–106 (1962).Google Scholar
  24. MacDonald, G. A.: Dissimilarity of continental and oceanic rock types. J. Petrology 1, 172–177 (1960).Google Scholar
  25. McDougall, I., and J. F. G. Wilkinson: Potassium-argon dates on some Cainozoic volcanic rocks from Northeastern New South Wales. J. Geol. Soc. Australia 14, 225–233 (1967).Google Scholar
  26. Muir, I. D., and C. E. Tilley: Mugearites and their place in alkali igneous rock series. J. Geol. 69, 186–203 (1961).Google Scholar
  27. Nockolds, S. R., and R. Allen: The geochemistry of some igneous rock series. Part 2. Geochim. et Cosmochim. Acta 5, 253–276 (1954).Google Scholar
  28. Norrish, K., and B. W. Chappell: X-ray fluorescence spectrography. In: Physical methods in determinative mineralogy (ed. J. Zussman). London: Academic Press 1967.Google Scholar
  29. Richards, H. C.: The volcanic rocks of South-Eastern Queensland. Proc. Roy. Soc. Queensland 27, 105–204 (1916).Google Scholar
  30. Stipp, J. J., and I. McDougall: Australian J. Sci. (in press).Google Scholar
  31. Taylor, S. R.: The application of trace element data to problems in petrology. Phys. Chem. of the Earth 6, 133–213 (1965).Google Scholar
  32. Thornton, C. P., and O. F. Tuttle: Chemistry of igneous rocks. I. The differentiation index. Am. J. Sci. 258, 664–684 (1960).Google Scholar
  33. Tilley, C. E., and I. D. Muir: Intermediate members of the oceanic basalt — trachyte association. Geol. Fören. i Stockholm Förh. 85, 434–443 (1964).Google Scholar
  34. Turner, F. J., and J. Verhoogen: Igneous and metamorphic petrology. New York: McGraw-Hill Book Co. 1960.Google Scholar
  35. Tuttle, O. F.: Optical studies on alkali feldspars. Am. J. Sci. 250 A, Bowen vol., 553–567 (1952).Google Scholar
  36. —, and N. L. Bowen: Origin of granite in the light of experimental studies in the system NaAlSi3O8-KAlSi3O8-SiO2-H2O. Geol. Soc. Am. Mem. 74, 1–153 (1958).Google Scholar
  37. Upton, B. G. J.: The geology of Tugtutoq and neighbouring islands, South Greenland. Part II Nordmarkitic syenites and related alkaline rocks. Medd. Grønland 169, no. 2 (1964).Google Scholar
  38. Watkins, N. D., and S. E. Haggerty: Primary oxidation variation and petrogenesis in a single lava. Contr. Mineral. and Petrol. 15, 251–271 (1967).Google Scholar
  39. Webb, A. W., N. C. Stevens, and I. McDougall: Isotopic age determinations on tertiary volcanic rocks and intrusions of South-Eastern Queensland. Proc. Roy. Soc. Queensland 79, 79–92 (1967).Google Scholar
  40. Wilkinson, J. F. G.: Clinopyroxenes of alkali olivine-basalt magma. Am. Mineralogist 41, 724–743 (1956).Google Scholar
  41. —: The clinopyroxenes of a differentiated teschenite sill near Gunnedah, New South Wales. Geol. Mag. 94, 123–134 (1957).Google Scholar
  42. Yagi, K.: The system acmite-diopside and its bearing on the stability relations of natural pyroxenes of the acmite-hedenbergite-diopside series. Am. Mineralogist 51, 976–1000 (1966).Google Scholar

Copyright information

© Springer-Verlag 1969

Authors and Affiliations

  • M. J. Abbott
    • 1
  1. 1.Department of Geology and MineralogyUniversity of QueenslandBrisbaneAustralia

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