Tectonic implications of Early Cretaceous low-Mg adakitic rocks generated by partial melting of thickened lower continental crust at the southern margin of the central North China Craton
Tectonic implications of Early Cretaceous low-Mg adakitic rocks generated by partial melting of thickened lower continental crust at the southern margin of the central North China Craton
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华北克拉通中部南缘加厚下陆壳部分熔融形成的早白垩世低镁埃达克岩的构造意义
DOI：
10.1016/j.gr.2015.11.013
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发表时间：
2016-10
影响因子：
6.1
通讯作者：
Yang Hao-Tian
中科院分区：
文献类型：
--
作者：
Yang De-Bin;Xu Wen-Liang;Zhao Guo-Chun;Huo Teng-Fei;Shi Jiang-Peng;Yang Hao-Tian
本文报道了中国中部三门峡-侯马地区早白垩世侵入岩的新全岩地球化学、Sr-Nd-Pb同位素以及锆石U-Pb和Hf同位素数据，并利用这些数据来约束该地区低镁埃达克岩（LMAR）的岩石成因以及深俯冲扬子板片在该地区三叠纪演化过程中影响的空间范围。新的锆石激光烧蚀电感耦合等离子体质谱（LA-ICP-MS）U-Pb数据表明，早、晚期的曲里、七里沟和高庙斑状石英闪长岩、蚕房花岗闪长岩和北部王茅斑状石英二长岩均侵位于早白垩世（~130Ma）和早白垩世晚期。 （~116Ma）。这些岩石的特征是高Na2O/K2O、Sr/Y和(La/Yb)n比率以及高Sr浓度、低Mg#[摩尔100×Mg/(Mg+Fe2+tot)]值以及低重稀土元素和Y浓度，所有这些都表明LMAR亲和力。这些样品具有相对较高的初始 87Sr/86Sr 比值 (0.7054–0.7095)，以及较低的 εNd(t)（−11.90 至 −22.20）和 εHf(t)（−16.7 至 −32.7）值，表明较低的大陆地壳起源。早白垩世LMAR内新元古代（754-542 Ma）和继承的晚三叠世（220 Ma）变质锆石的存在以及这些岩石相对较高的206Pb/204Pb比率表明它们是由经历了超高压变质作用的扬子克拉通（YC）基底材料部分熔融的原生岩浆形成的。相比之下，该地区早白垩世LMAR内存在古元古代和太古代继承性锆石，并且这些岩石的206Pb/204Pb比值相对较低，这表明这些岩石源自华北克拉通（NCC）增厚的下陆壳部分熔融所产生的原生岩浆。这些岩石可能是在与软流圈地幔物质上涌相关的伸展环境中形成的。三门峡-侯马地区华北克拉通内存在YC基底物质表明，三叠纪期间，深俯冲的扬子板片影响了华北克拉通中部南缘横向范围约100公里的区域。
This paper reports new whole-rock geochemical, Sr–Nd–Pb isotopic, and zircon U–Pb and Hf isotopic data for Early Cretaceous intrusive rocks in the Sanmenxia–Houma area of central China, and uses these data to constrain the petrogenesis of low-Mg adakitic rocks (LMAR) and the spatial extent of the influence of the deeply subducted Yangtze slab during the Triassic evolution of this region. New zircon laser-ablation inductivity coupled plasma mass spectrometry (LA-ICP-MS) U–Pb data indicate that the early- and late-stage southern Quli, Qiligou, and Gaomiao porphyritic quartz diorites, the Canfang granodiorite, and the northern Wangmao porphyritic quartz monzodiorite were emplaced during the Early Cretaceous (~ 130 Ma) and the late Early Cretaceous (~ 116 Ma). These rocks are characterized by high Na2O/K2O, Sr/Y, and (La/Yb)nratios as well as high Sr concentrations, low Mg#[molar 100 × Mg/(Mg + Fe2 +tot)] values, and low heavy rare earth element and Y concentrations, all of which indicate an LMAR affinity. The samples have relatively high initial87Sr/86Sr ratios (0.7054–0.7095), and low εNd(t) (− 11.90 to − 22.20) and εHf(t) (− 16.7 to − 32.7) values, indicative of a lower continental crust origin. The presence of Neoproterozoic (754–542 Ma) and inherited Late Triassic (220 Ma) metamorphic zircons within the late Early Cretaceous LMAR and the relatively high206Pb/204Pb ratios of these rocks suggest that they formed from primary magmas derived from partial melting of Yangtze Craton (YC) basement material that had undergone ultrahigh-pressure metamorphism. In contrast, the presence of Paleoproterozoic and Archean inherited zircons within early Early Cretaceous LMAR in this area and the relatively low206Pb/204Pb ratios of these rocks are indicative of derivation from primary magmas generated by partial melting of the thickened lower continental crust of the North China Craton (NCC). These rocks may have formed in an extensional environment associated with the upwelling of asthenospheric mantle material. The presence of YC basement material within the NCC in the Sanmenxia–Houma area suggests that the deeply subducted Yangtze slab influenced an area of ~ 100 km in lateral extent within the southern margin of the central NCC during the Triassic.
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影响因子：
3
作者：
F. Pei;Wenliang Xu;De‐Bin Yang;Yang Yu;Wei Wang;Quan-guo Zhao
通讯作者：
F. Pei;Wenliang Xu;De‐Bin Yang;Yang Yu;Wei Wang;Quan-guo Zhao
华北克拉通东南缘新元古代基性岩浆作用——来自徐州—淮北地区辉绿岩群锆石全岩地球化学和U-Pb、Hf同位素研究的证据
DOI：
10.1007/s11430-011-4237-7
发表时间：
2012-06
期刊：
Science China Earth Sciences
影响因子：
--
作者：
Wang QingHai;Yang DeBin;Xu WenLiang
通讯作者：
Xu WenLiang
影响因子：
2.9
作者：
R. Zartman;B. Doe
通讯作者：
R. Zartman;B. Doe
影响因子：
5.3
作者：
STEIGER, RH;JAGER, E
通讯作者：
JAGER, E
影响因子：
6.1
作者：
P. Peng;M. Zhai;Qiu-li Li;Fu-guan Wu;Quanlin Hou;Zhong Li;Tiesheng Li;Yanbin Zhang
通讯作者：
P. Peng;M. Zhai;Qiu-li Li;Fu-guan Wu;Quanlin Hou;Zhong Li;Tiesheng Li;Yanbin Zhang