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篇目详细内容 |
【篇名】 |
Post-collisional adakitic biotite plagiogranites from Guangtoushan pluton (Mianxian, central China): Petrogenesis and tectonic implication |
【刊名】 |
Frontiers of Earth Science in China |
【刊名缩写】 |
Front. Earth Sci. China |
【ISSN】 |
1673-7385 |
【EISSN】 |
1673-7490 |
【DOI】 |
10.1007/s11707-007-0036-z |
【出版社】 |
Higher Education Press and Springer-Verlag |
【出版年】 |
2007 |
【卷期】 |
1
卷3期 |
【页码】 |
299-303
页,共
5
页 |
【作者】 |
QIN Jiangfeng;
LAI Shaocong;
LI Yongfei;
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【关键词】 |
Guangtoushan; biotite plagiogranite; adakite; petrogenesis; post-collision |
【摘要】 |
The post-collisional Guangtoushan pluton intruded into the Mianlue suture, Central China. Geochemically, the Guangtoushan biotite plagiogranites show many close compositional similarities to high-silica adakites from the supra-subduction zone setting, but tend to have a higher concentration of K2O (3.22%–3.84%). Chondrite-normalized rare earth element patterns are characterized by high ratios of (La/Yb)N, concave-upward shapes of the heavy rare earth element (HREE), and a lack of significant Eu anomalies. In conjunction with high abundances of Ba and Sr, as well as low abundances of Y and HREE, these patterns suggest a feldspar-poor, garnet±amohibole-rich fractionation mineral assemblage. Coupled with previous studies, we suggest that the Guangtoushan biotite plagiogranites were likely to be caused by subducting slab break-off during the late orogenic stage in the West Qinling orogenic belt. |
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