中国科学院机构知识库网格
Chinese Academy of Sciences Institutional Repositories Grid
Petrogenesis of Late Paleozoic diorites and A-type granites in the central Eastern Tianshan, NW China: Response to post-collisional extension triggered by slab breakoff

文献类型:期刊论文

作者Du, Long1,2,3; Long, Xiaoping1; Yuan, Chao2; Zhang, Yunying2; Huang, Zongying2; Sun, Min4; Xiao, Wenjiao5
刊名LITHOS
出版日期2018-10-01
卷号318页码:47-59
关键词A-type granite Post-collisional Slab breakoff Eastern Tianshan Central Asian Orogenic Belt
ISSN号0024-4937
DOI10.1016/j.lithos.2018.08.006
英文摘要Geological evolution of the Eastern Tianshan in the Late Paleozoic is significant to understanding the multiple accretions and final formation of the southern Central Asian Orogenic Belt. Here, we report new whole-rock geochemical and Sr-Nd is otopic data, and in situ zircon U-Pb ages for three typical A-type granitic intrusions (syenogranite, K-feldspar granite and monzonitic granite) and one dioritic pluton in the central Eastern Tianshan, NW China, in order to constrain their petrogenesis, tectonic setting and geodynamic evolution. Zircon LA-ICP-MS U-Pb ages indicate that the syenogranites and K-feldspar granites were both formed during a short time interval in the Early Permian (284-286 Ma), whereas the diorites were crystallized at 293 +/- 6 Ma. The monzonitic granites were generated at 307 +/- 3 Ma, earlier than the other two granitic intrusions. The three kinds of granites (syenogranite, K-feldspar granite and monzonitic granite) have high HFSE, HREE and Y/Nb ratios (1.68-2.84), and remarkably low Sr and Ba contents, with the absence of aluminium-rich minerals and show metaluminous to weakly peraluminous natures, indicating geochemical characteristics of aluminous A(2)-type granites. These granites show negative epsilon(Nd)(t) (-3.32 to -4.40) values and Mesoproterozoic two stage Nd model ages (T-DM(2) = 1.36 to 1.43 Ga), which suggest a relatively old crustal source for these rocks. The Sr-Nd isotopic compositions imply that the Mesoproterozoic metamorphic basement of the Central Tianshan Block can be considered as a potential magmatic source for these aluminous A(2)-type granites. In addition, they have geochemical characteristics similar to the experimental melt that was derived from partial melting of crustal metaigneous rocks at the depth of middle to lower crust levels. Therefore, the granites were most likely produced by partial melting of metaigneous rocks in a post-collisional extensional setting. The diorites have low SiO2 and high MgO, with uniform (Sr-87/Sr-86)(i) values (similar to 0.7055), negative epsilon(Nd)(t) values (-4.11 to -4.59) and Mesoproterozoic two stage Nd model ages (T-DM(2) = 1.41 to 1.45 Ga). They have higher Ti/Zr (42.8-46.7) and Ti/Y (280-359) ratios than continental crust and show negative Nb-Ta-Ti anomalies, which can be explained by partial melting of a relatively fertile mantle modified by old crustal materials of the Central Tianshan Block. The formation of the dioritic pluton was induced by an upwelling asthenosphere in an extensional geodynamic setting. Based on the zircon saturation temperatures of these A-type granites and the distribution of Late Carboniferous to Early Permian mantle derived intrusions, a slab breakoff model is suggested to interpret the formation of the studied A-type granites and diorites. We infer that the slab breakoff was initiated in the Late Carboniferous and ended in the Early Permian. (C) 2018 Elsevier B.V. All rights reserved.
WOS关键词ASIAN OROGENIC BELT ; LARGE IGNEOUS PROVINCE ; AQISHAN-YAMANSU BELT ; MA MANTLE PLUME ; ZIRCON U-PB ; GEOCHEMICAL CONSTRAINTS ; TECTONIC IMPLICATIONS ; SOUTHEASTERN AUSTRALIA ; GEODYNAMIC EVOLUTION ; NORTHWESTERN CHINA
资助项目National Basic Research Program of China[2014CB440801] ; National Natural Science Foundation of China[41421002] ; National Natural Science Foundation of China[41522202] ; National Natural Science Foundation of China[41603028] ; MOST Special Fund from the State Key Laboratory of Continental Dynamics
WOS研究方向Geochemistry & Geophysics ; Mineralogy
语种英语
WOS记录号WOS:000449141300004
出版者ELSEVIER SCIENCE BV
资助机构National Basic Research Program of China ; National Basic Research Program of China ; National Natural Science Foundation of China ; National Natural Science Foundation of China ; MOST Special Fund from the State Key Laboratory of Continental Dynamics ; MOST Special Fund from the State Key Laboratory of Continental Dynamics ; National Basic Research Program of China ; National Basic Research Program of China ; National Natural Science Foundation of China ; National Natural Science Foundation of China ; MOST Special Fund from the State Key Laboratory of Continental Dynamics ; MOST Special Fund from the State Key Laboratory of Continental Dynamics ; National Basic Research Program of China ; National Basic Research Program of China ; National Natural Science Foundation of China ; National Natural Science Foundation of China ; MOST Special Fund from the State Key Laboratory of Continental Dynamics ; MOST Special Fund from the State Key Laboratory of Continental Dynamics ; National Basic Research Program of China ; National Basic Research Program of China ; National Natural Science Foundation of China ; National Natural Science Foundation of China ; MOST Special Fund from the State Key Laboratory of Continental Dynamics ; MOST Special Fund from the State Key Laboratory of Continental Dynamics
源URL[http://ir.iggcas.ac.cn/handle/132A11/89423]  
专题地质与地球物理研究所_岩石圈演化国家重点实验室
通讯作者Long, Xiaoping
作者单位1.Northwest Univ, Dept Geol, State Key Lab Continental Dynam, Xian 710069, Shaanxi, Peoples R China
2.Chinese Acad Sci, Guangzhou Inst Geochem, State Key Lab Isotope Geochem, Guangzhou 510640, Guangdong, Peoples R China
3.Shandong Univ Sci & Technol, Coll Geol Sci & Engn, Qingdao 266590, Peoples R China
4.Univ Hong Kong, Dept Earth Sci, Pokfulam Rd, Hong Kong, Hong Kong, Peoples R China
5.Chinese Acad Sci, Inst Geol & Geophys, State Key Lab Lithospher Evolut, Beijing 100029, Peoples R China
推荐引用方式
GB/T 7714
Du, Long,Long, Xiaoping,Yuan, Chao,et al. Petrogenesis of Late Paleozoic diorites and A-type granites in the central Eastern Tianshan, NW China: Response to post-collisional extension triggered by slab breakoff[J]. LITHOS,2018,318:47-59.
APA Du, Long.,Long, Xiaoping.,Yuan, Chao.,Zhang, Yunying.,Huang, Zongying.,...&Xiao, Wenjiao.(2018).Petrogenesis of Late Paleozoic diorites and A-type granites in the central Eastern Tianshan, NW China: Response to post-collisional extension triggered by slab breakoff.LITHOS,318,47-59.
MLA Du, Long,et al."Petrogenesis of Late Paleozoic diorites and A-type granites in the central Eastern Tianshan, NW China: Response to post-collisional extension triggered by slab breakoff".LITHOS 318(2018):47-59.

入库方式: OAI收割

来源:地质与地球物理研究所

浏览0
下载0
收藏0
其他版本

除非特别说明,本系统中所有内容都受版权保护,并保留所有权利。