Mineralogy, Geochemistry and Geotectonic of Plagiogranites from Shahre-Babak Ophiolite, Zagros Zone, Iran
Shahre-Babak ophiolite is a part of the inner Zagros ophiolite belt in Iran.Major parts of intrusive masses of Share-Babak ophiolite are gabbro and plagiogranite.The SiO2 versus Na2O+K2O diagram shows that the palgiogranites are related to calk-alkaline series.Rare earth elements exhibit relatively similar pattern that indicates these rocks are syngenetic.Also, REE patterns display an enrichment of LREE compared to HREE, and arc characterized by flat to slightly concave-up patterns from Gd to Yb.Such patterns contrast sharply with those of plagiogranites in more complete ophiolite sequences, such as the Semail ophiolite, Oman, or the Troodos ophiolite, Cyprus, and Neyriz, where patterns are much flatter and slightly LREE-depleted.The slightly LREE-enriched patterns of the Shahre-Babak plagiogranites support a partial melting origin for them.The low TiO2, Nb, Ta content and high LREE concentrations of the Shahre-Babak plagiogranites indicate that the rocks were likely derived from the anatexis of amphibolites, which were related to hydrothermal alteration of gabbros in intra-oceanic back-arc basin.
plagiogranite back-arc basin Share-Babak ophiolite Neo-Tethys Iran
Fatemeh Sepidbar Hassan Mirnejad
Department of Geology, University of Tehran, Tehran 14155-64155, Iran Department of Geology, University of Tehran, Tehran 14155-64155, Iran;Department of Earth and Enviro
国际会议
武汉
英文
507-518
2015-10-16（万方平台首次上网日期，不代表论文的发表时间）