Document Type : Original Research Paper

Authors

1 Islamic Azad University, Science and Research Branch, Tehran, Iran

2 Islamic Azad University, Lahijan, Iran

3 Shahid Beheshti University, Tehran, Iran

4 Geological Survey of Iran, Tehran, Iran

Abstract

     Petrological,geochemical and isotropic evidence of crustal contamination of the Quaternary basic rocks of Ghorveh-Takab axis is presented in this paper. These rocks are olivine basalt and basalt and they are plotted in the field of alkaline suites in geochemical diagrams.
Some evidence, such as the presence of gneissic xenoliths, quartz xenocrysts with reaction rims and biotite phenoblasts in the basic rocks of the study area and high amount of potassium and high values of   ratios, high concentration of LREE in comparison with HREE, high values of  ratios and low values of   ratios all indicate the crustal contamination of basic magma during its ascent.

Keywords

References
Basaltic volcanism study project,  1981-  Basaltic Volcanism on the Terrestrial Planets. Pergamon Press.
Best, Myron G., 2001- Igneous Petrology, W.H. Freeman and Company, NewYork.
Carlson, R. W., Hart, W. K., 1988. Flood basalt Volcanism in the north western United States. Continental Flood Basalts, J.D. MacDougall (ed.), Kluwer Academic Publishers, 273-310.
Cox, K. G., Bell J. D.,  Pankhurst, R . J., 1979-  The Interpertation of Igneous Rocks. Allen and Unwin, London. 450 P.
DePaolo, D.J. and Wasserburg, G. J., 1979- Nd isotopes in Flood basalts from the Siberian platform and inferences about their mantle sources. Proceedings of National Academy of Science, USA, 76, 3056-3060.
Nelson, S. A., 2003- Magmatic  Differentiation.
www.tulane.edu/~sanelson/geo1212/magmadiff.htm
Tatsumi and Eggins, 1995- continental crust formation by Complementary accumulation of formation by complementary accumulation of the enriched mantle, Boston, Blackwell Science. 211 P.