108 / 2016-11-26 20:20:32

Geochemistry of the Xiaojiashan Tungsten Deposit Intrusive Rocks in the Barkol district, Xinjiang, and Its Tectonic Setting

Granite, Geochemistry, Tectonic setting, Xiaojiashan, Xinjiang

The Xiaojiashan Tungsten deposit is located in Barkol district, Xinjiang. The ore bodies occur in the Hercynian granite intrusions and contact between the intrusion and wallrock which consists of the second lithologic section of the first Sub-Formation in Middle Devonian Dananhu Formation (D2d12). A systematic study on the composition of major element, trace element, REE of the intrusive rocks from the Xiaojiashan, reveals their lithogeochemical feature, source material, tectonic setting and geological significance. Biotite granite and cataclastic granite are the two most widely distributed intrusive bodies in Xiaojiashan tungsten deposit. The granite belongs to peraluminous A-type granite with high potassic calc-alkaline series, and all rocks show light REE enriched patterns and they are resulted from the comagmatic evolution. The trace element characters suggest that crystallization differentiation might even occur in the diagenetic process, and the magmatic origin may be connected to the enriched lithospheric mantle source. The granite belongs to post-collisional extension granite and the rocks formed in an extensional tectonic environment, and it might result from magma activity in such an extensional tectonic environment.