| Sr-Nd-Pb isotopic compositions of the lower crust beneath northern Tarim: insights from igneous rocks in the Kuluketage area, NW China | |
| Zhang, Yan1,2; Wei, Xun1,2,3; Xu, Yi-Gang4; Long, Xiao-Ping5; Shi, Xue-Fa1,2; Zhao, Jian-Xin6; Feng, Yue-Xing6 | |
| 2017-04-01 | |
| 发表期刊 | MINERALOGY AND PETROLOGY
 |
| 卷号 | 111期号:2页码:237-252 |
| 文章类型 | Article |
| 摘要 | The composition of lower crust of the Tarim Craton in NW China is essential to understand the petrogenesis of the similar to 290-275 Ma Tarim basalts and associated intermediate-felsic rocks. However, it remains poorly constrained because extremely sparse granulite terrains or granulite xenoliths have been found in the Tarim Craton. New trace element and Sr-Nd-Pb isotopic data are reported for the Neoarchean and Neoproterozoic igneous rocks widely distributed in the northern margin of the Tarim Craton. The Neoarchean granitic gneisses show fractionated REE (rare earth element) patterns [(La/Yb) (N) = 12-58, Yb-N = 10.6-36] with pronounced negative Nb-Ta and Ti anomalies. These features, together with negative epsilon Nd-i (-0.7 to -3.2) suggest that they were derived from melting of mafic lower crust. The Neoproterozoic biotite granodiorites are strongly depleted in HREE with (La/Yb) (N) up to 55. They are characterized by high Sr (671-789 ppm) but very low Y (7.10-8.06 ppm) and Yb contents (0.47-0.58 ppm), showing typical features of adakitic rocks. The samples with different SiO2 contents display identical Sr-87/Sr-86(i) (0.7101-0.7103), epsilon Nd-i (-14.1 to -15.7) and Pb isotopes (Pb-208/Pb-204(i) = 36.94-37.07). These features together with arc-like trace element patterns suggest that they were derived from melting of thickened lower crust. In comparison, the Neoproterozoic hornblende-biotite granodiorites have similar trace element compositions except for weaker depletion in HREE and have lower Sr-87/Sr-86(i) (0.7078) and initial Pb isotopes, and higher epsilon Nd-i (-12.3 to -12.7). This suggests that they were formed by melting of old lower continental crust at a shallower depth than the biotite granodiorites. These rocks were derived from the lower crust, thus providing valuable information on the nature of the lower crust beneath northern Tarim. Combined with published data, the Sr-87/Sr-86(i), epsilon Nd-i, Pb-206/Pb-204(i) and epsilon Hf-i of the northern Tarim lower crust ranges from 0.7055 to 0.7103, from -12 to -17, from 16.20 to 16.65, and from -7 to -19, respectively, at similar to 785 Ma. These data also suggest vertical compositional heterogeneity of the northern Tarim lower crust. |
| 关键词 | Tarimcraton Lower Crust Sr-nd-pb-hf Isotopic Compositions Adakiticrocks |
| DOI | 10.1007/s00710-016-0470-2 |
| 收录类别 | SCI |
| 语种 | 英语 |
| WOS记录号 | WOS:000398842400005 |
| 引用统计 | |
| 文献类型 | 期刊论文 |
| 版本 | 出版稿 |
| 条目标识符 | http://ir.qdio.ac.cn/handle/337002/136708 |
| 专题 | 海洋地质与环境重点实验室 |
| 作者单位 | 1.State Ocean Adm, Inst Oceanog 1, Key Lab Marine Sedimentol & Environm Geol, Qingdao 266061, Peoples R China 2.Qingdao Natl Lab Marine Sci & Technol, Lab Marine Geol, Qingdao 266061, Peoples R China 3.Chinese Acad Sci, Inst Oceanol, Key Lab Marine Geol & Environm, Qingdao 266071, Peoples R China 4.Chinese Acad Sci, Guangzhou Inst Geochem, State Key Lab Isotope Geochem, Guangzhou 510640, Guangdong, Peoples R China 5.Northwest Univ, Dept Geol, State Key Lab Continental Dynam, Xian 710069, Peoples R China 6.Univ Queensland, Radiogen Isotope Facil, Sch Earth Sci, Brisbane, Qld 4072, Australia |
| 推荐引用方式 GB/T 7714 | Zhang, Yan,Wei, Xun,Xu, Yi-Gang,et al. Sr-Nd-Pb isotopic compositions of the lower crust beneath northern Tarim: insights from igneous rocks in the Kuluketage area, NW China[J]. MINERALOGY AND PETROLOGY,2017,111(2):237-252. |
| APA | Zhang, Yan.,Wei, Xun.,Xu, Yi-Gang.,Long, Xiao-Ping.,Shi, Xue-Fa.,...&Feng, Yue-Xing.(2017).Sr-Nd-Pb isotopic compositions of the lower crust beneath northern Tarim: insights from igneous rocks in the Kuluketage area, NW China.MINERALOGY AND PETROLOGY,111(2),237-252. |
| MLA | Zhang, Yan,et al."Sr-Nd-Pb isotopic compositions of the lower crust beneath northern Tarim: insights from igneous rocks in the Kuluketage area, NW China".MINERALOGY AND PETROLOGY 111.2(2017):237-252. |
| 条目包含的文件 | ||||||
| 文件名称/大小 | 文献类型 | 版本类型 | 开放类型 | 使用许可 | ||
| Sr-Nd-Pb isotopic co（5938KB） | 期刊论文 | 出版稿 | 限制开放 | CC BY-NC-SA | 浏览 | |
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。
修改评论