Chinese Science Bulletin

, Volume 46, Issue 14, pp 1215–1219 | Cite as

Almandine megacrysts from Yingfengling Cenozoic basalt in Leizhou Peninsula and their parental magma origin

  • Jinhai Yu
  • S. Y. O’Reilly
Notes
Received:

Abstract

The garnet megacrysts from Yingfengling basalts are characterized by high FeO (>20%), CaO (7.02% –8.16%) and low MgO (5.88%–10.87%). Significant composition variations are observed in these megacrysts, of which Ni, V, Sc, Co, and HREE are positively correlated with their Mg#, and Zr, Hf, Ga, Y, Sr, Nb, Zn and LREE-MREE are negatively correlated with Mg#. Megacryst parent magma is a highly evolved residual melt with strongl depletion in Ti, Sr, Hf, Nb and HREE. This parental magma was generated by more than 60% of crystallization fractionation of clinopyroxene, garnet, plagioclase and ilmenite from quartz tholeiitic magma. It has not erupted to the surface, but stayed at the upper mantle and formed the megacrystic cumulate. Megacrysts and their host basalt are in disequilibrium.

Keywords

almandine megacryst geochemistry LAM-ICPMS Leizhou Peninsula 
This is a preview of subscription content, log in to check access.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    Irving, A. J., Frey, F. A., The distribution of trace elements between garnet megacrysts and volcanic liquids of kimberlitic to rhyolitic composition, Geochim. Cosmochim. Acta, 1978, 42: 771.CrossRefGoogle Scholar
  2. 2.
    Upton, B. G. J., Hinton, R. W., Aspen, P. et al., Megacrysts and associated xenoliths: evidence for migration of geochemically enriched melts in the upper mantle beneath Scotland, J. Petrol., 1999, 40: 935.CrossRefGoogle Scholar
  3. 3.
    Bindeman, I. N., Bailey, J. C., Trace elements in anorthite megacrysts from the Kurile Island arc: a window to across-arc geochemical variations in magma compositions, Earth Planet. Sci. Lett, 1999, 169: 209.CrossRefGoogle Scholar
  4. 4.
    Dobosi, G., Jenner, G. A., Petrologic implications of trace element variation in clinopyroxene megacrysts from the Nograd volcanic province, north Hungary: a study by laser ablation microprobeinductively coupled plasma-mass spectrometry, Lithos., 1999, 46: 731.CrossRefGoogle Scholar
  5. 5.
    E. M. -L., Zhao, D. S., Cenozoic Basalts and Deep-seated Xenoliths in Eastern China (in Chinese with English abstract), Beijing: Science Press, 1987, 490.Google Scholar
  6. 6.
    Chi, J. S., The study of Cenozoic Basalts and Upper Mantle Beneath Eastern China (attachment: kimberlites) (in Chinese with English abstract), Wuhan: China University of Geosciences Press, 1988.Google Scholar
  7. 7.
    Liu, C. Q., Masuda, A., Xie, G. H., Isotope and trace element geochemistry of alkali basalts and associated megacrysts from the Huangyishan volcano, Kuandian, Liaoning, NE China, Chemical Geology, 1992, 97: 219.CrossRefGoogle Scholar
  8. 8.
    Dong, Z., Pyropes from China: Peridotite xenoliths from kimberlites versus megacrysts in basalts, International Geol. Review, 1997, 39: 141.CrossRefGoogle Scholar
  9. 9.
    Yu, J. H., Fang, Z., Zhou, X. et al., Garnet granulite facies xenoliths from Yingfengling Cenozoic basalt in Leizhou, Guangdong Province, Chinese Science Bulletin, 1998, 43(23): 2013.CrossRefGoogle Scholar
  10. 10.
    Yu, J. H., Luo, S., Megacrysts from Cenozoic Yingfengling basalt in Leizhou Peninsula, South China Mineral Acta (in Chinese with English abstract), 2000, 20(2): 191.Google Scholar
  11. 11.
    Norman, M. D., Melting and metasomatism in the continental lithosphere: laser ablation ICPMS analysis of minerals in spinel lherzolites from eastern Australia, Contrib. Mineral. Petrol., 1998, 130: 240.CrossRefGoogle Scholar
  12. 12.
    Wood, B. J., Blundy, J. D., A predictive model for rare earth element partioning between clinopyroxene and anhydrous silicate melt, Contrib. Mineral. Petrol., 1997, 129: 166.CrossRefGoogle Scholar
  13. 13.
    Johnson, K. T. M., Experimental determination of partition coefficients for rare earth and high-field-strength elements between clinopyroxene, garnet and basaltic melt at high pressure, Contrib. Mineral. Petrol., 1998, 133: 60.CrossRefGoogle Scholar
  14. 14.
    Zhu, B., Wang, H., Nd-Sr-Pb isotopic and chemical evidence for the volcanism with MORB-OIB source characteristics in the Leiqiong area, China, Geochimica (in Chinese with English abstract), 1989, 18(3): 193.Google Scholar
  15. 15.
    Liu, C., Xie, G., Masuda, A., Geochemistry of Cenozoic basalts from eastern China--I. Major element and trace element compositions: petrogenesis and characteristics of mantle source, Geochimica (in Chinese with English abstract), 1995, 24(1): 1.Google Scholar
  16. 16.
    Flower, M. F. J., Zhang, M., Chen, C. Y. et al., Magmatism in the South China Basin 2. Post-spreading Quaternary basalts from Hainan Island, South China, Chemical Geology, 1992, 97: 65.CrossRefGoogle Scholar
  17. 17.
    Kushiro, I., Compositions of partial melts formed in mantle peridotites at high pressures and their relation to those of primitive MORB, Phys. Earth. Planet. Inter., 1998, 107: 103.CrossRefGoogle Scholar
  18. 18.
    Paster, T. P., Schauwecker, D. S., Haskin, L. A., The behavior of some trace elements during solidification of the Skaergaard Layered Series, Geo. Cos. Avta, 1974, 38: 1549.CrossRefGoogle Scholar

Copyright information

© Science in China Press 2001

Authors and Affiliations

  • Jinhai Yu
    • 1
  • S. Y. O’Reilly
    • 2
  1. 1.National Key Laboratory of Metallogenic Mechanism of Endogenetic Deposits, Department of Earth SciencesNanjing UniversityNanjingChina
  2. 2.National Key Center of GEMOC, Department of Earth and Planetary SciencesMacquarie UniversityNorth RydeAustralia

Personalised recommendations