Scientific Quarterly Journal of Geosciences

Scientific Quarterly Journal of Geosciences

Magmatic Evolution in Quaternary Basaltic Rocks in Ghorveh – Takab Axis

Document Type : Original Research Paper

Authors
S. Malecootyan 1
Sh. Hagh-Nazar 2
M. Ghorbani 3
M. H Emami 4
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
10.22071/gsj.2008.58267
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
Sr isotope
Nd isotope
Crustal contamination
References
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Scientific Quarterly Journal of Geosciences
Volume 16, Issue 64
Winter 2007
Pages 166-178