Zircon U-Pb Age and Geochemistry of the Ore-hosting Ultramafic Complex of Zhou'an PGE-Cu-Ni Deposit,Henan Province,Central China  

作　　者：YAN Haiqing DING Ruiying TANG Zhongli WANG Yalei LIU Shuang MA Jiahong HU Yanqiang CHEN Kena 

机构地区：[1]College of Earth Science and Resource,Chang'An University [2]College of Resource and Environmental Science,Lanzhou University [3]Key Laboratory of Western China's Mineral Resources and Geological Engineering,Ministry of Education [4]815 Geological Team of East China Metallurgical and Geological Exploration Bureau

出　　处：《Acta Geologica Sinica(English Edition)》2012年第6期1479-1487,共9页地质学报（英文版）

基　　金：granted by the National Natural Science Fund of China (No. 41072058);the Scientific Research Special Subject for Public Welfare Profession (200911007 and201011058);China central college fund(CHD2011TD007)

摘　　要：The Zhou＇an PGE-Cu-Ni deposit was recently discovered in the Qinling orogenic belt bound by the Yangtze and the North China Cratons. It is a blind deposit thoroughly covered by the Cenozoic alluvial sediments in the Nanyang Basin. As the first large PGE-Cu-Ni deposit discovered in the Qinling-Dabie-Sulu orogenic belt, its geological and geochemical characteristic, isotope age, genesis and tectonic setting are of wide concern in both scientific studies and ore exploration. In this contribution, we report the results obtained from a pioneering study. The Zhou＇an ultramafic complex is ferruginous, with m/f = 4.79-5.08, and shows the nature of tholeiite series. It is rich in light rare earth elements, Rb, Th, U, La, Sm, Zr and Hf, and poor in heavy rare earth elements, Nd and Ta, suggesting an intraplate setting. It has high S7Sr/S6Sr and low 143Nd/144Nd ratios. The ratios of Zr/Nb, La/Nb, Ba/ Nb, Rb/Nb, Th/Nb, Th/La and Ba/La, suggest the magma originated from lithosphere mantle. The Fo values of olivine and Pd/Ir-Ni/Cu diagram suggest primary magma was High Mg basalt. The laser ablation inductively coupled plasma atomic emission spectroscopy zircon U-Pb age is 641.5 ± 3.7 Ma.The Zhou＇an PGE-Cu-Ni deposit was recently discovered in the Qinling orogenic belt bound by the Yangtze and the North China Cratons. It is a blind deposit thoroughly covered by the Cenozoic alluvial sediments in the Nanyang Basin. As the first large PGE-Cu-Ni deposit discovered in the Qinling-Dabie-Sulu orogenic belt, its geological and geochemical characteristic, isotope age, genesis and tectonic setting are of wide concern in both scientific studies and ore exploration. In this contribution, we report the results obtained from a pioneering study. The Zhou＇an ultramafic complex is ferruginous, with m/f = 4.79-5.08, and shows the nature of tholeiite series. It is rich in light rare earth elements, Rb, Th, U, La, Sm, Zr and Hf, and poor in heavy rare earth elements, Nd and Ta, suggesting an intraplate setting. It has high S7Sr/S6Sr and low 143Nd/144Nd ratios. The ratios of Zr/Nb, La/Nb, Ba/ Nb, Rb/Nb, Th/Nb, Th/La and Ba/La, suggest the magma originated from lithosphere mantle. The Fo values of olivine and Pd/Ir-Ni/Cu diagram suggest primary magma was High Mg basalt. The laser ablation inductively coupled plasma atomic emission spectroscopy zircon U-Pb age is 641.5 ± 3.7 Ma.

关 键 词：zircon U-Pb age GEOCHEMISTRY ultramafic body PGE-Cu-Ni deposit tectonic setting 

分 类 号：P597.3[天文地球—地球化学]