Geochemical, mineralogical and chronological studies of mafic-intermediate dykes in the Jiaodong Peninsula: implications for Late Mesozoic mantle source metasomatism and lithospheric thinning of the eastern North China Craton
Geochemical, mineralogical and chronological studies of mafic-intermediate dykes in the Jiaodong Peninsula: implications for Late Mesozoic mantle source metasomatism and lithospheric thinning of the eastern North China Craton
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胶东半岛镁铁质中脉岩地球化学、矿物学和年代学研究：对华北克拉通东部晚中生代地幔源交代作用和岩石圈减薄的启示
DOI：
10.1080/00206814.2019.1692253
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发表时间：
2020-12
影响因子：
2.6
通讯作者：
Yinghuai Lu
中科院分区：
文献类型：
--
作者：
Xuefei Liu;Jun Deng;Yayun Liang;Qingfei Wang;Gongjian Li;Yao Ma;Lijuan Xu;Yinghuai Lu
摘要中国东部克拉顿（NCC）的晚期中生代构造演变仍然有争议。在这项研究中，在东北NCC的同一部分中发现的一组早白垩纪木质陷阱堤防群是U
ABSTRACT The Late Mesozoic tectonic evolution of the eastern North China Craton (NCC) remains controversial. In this study, a suite of Early Cretaceous mafic-intermediate dyke swarms found in the same section in the Jiaodong Peninsula, eastern NCC, were used to trace the nature of lithospheric mantle and crust–mantle interaction. Zircon U-Pb dating demonstrates that these dykes emplaced into the Jiaodong Peninsula during the same period (112–121 Ma). Diorite dykes have SiO2 contents of 52.7–54.1 wt.%, Na2O+K2O contents of 5.77–6.10 wt.%, a limited range of MgO (4.43–5.13 wt.%), Cr (64.8–85.5 ppm) and Ni (23.6–27.7 ppm), and a narrow range of (87Sr/86Sr)i isotopic ratios (0.709240–0.709246), ƐNd(t) values (−20.0 to −19.1) and ƐHf(t) values (ca. −23.9). Lamprophyre and dolerite dykes have low contents of SiO2 (50.5–55.4 wt.%) and Na2O+K2O (4.88–7.28 wt.%), high contents of Al2O3 (14.6–15.8 wt.%), MgO (5.83–8.60 wt.%), Cr (210–292 ppm) and Ni (114–149 ppm), and a narrow range (87Sr/86Sr)i isotopic ratios (0.709134–0.709788), ƐNd(t) values (−19.9 to −17.4) and ƐHf(t) values (−22.1 to −15.1). Both intermediate and mafic dykes exhibit strong large ion lithophile elements (LILE) enrichment and high field strength element (HFSE) depletion. These geochemical characteristics demonstrate that the magma was primarily derived from relatively low degrees of the partial melting of garnet-lherzolite mantle, which was modified by fluids from a subducting oceanic slab with marine sediments. Both the mafic dykes and intermediate dykes originated from the same magma source and formed in different stages of magma fractionation crystallization. The magma experienced the fractional crystallization of clinopyroxene and more ferromagnesian minerals in a hydrous condition, thus forming mafic dykes. Then, the residual calc-alkaline liquids upwelled into a low-H2O and low-pressure environment, in which more plagioclase crystallized from liquid, thus increasing the degree of differentiation and producing the Ca- and Al-rich diorite dyke. Combined with Late Mesozoic mantle-derived mafic-intermediate dykes and crust-derived volcanic rocks in the region, the eastern NCC has experienced considerable lithospheric thinning along with regional extensional tectonics, which was caused by the prolonged thermo-mechanical-chemical erosion on the lithosphere induced by the rollback of the subducted paleo-Pacific plate. Graphic abstract
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影响因子：
3.8
作者：
Jian‐Bo Zhou;S. Wilde;Guochun Zhao;Changqing Zheng;W. Jin;Xingzhou Zhang;Hongjiang Cheng
通讯作者：
Jian‐Bo Zhou;S. Wilde;Guochun Zhao;Changqing Zheng;W. Jin;Xingzhou Zhang;Hongjiang Cheng
影响因子：
3.9
作者：
Jin-Hui Yang;Fu-Yuan Wu;Sun‐Lin Chung;S. Wilde;M. Chu;C. Lo;B. Song
通讯作者：
Jin-Hui Yang;Fu-Yuan Wu;Sun‐Lin Chung;S. Wilde;M. Chu;C. Lo;B. Song
世界级新城金矿：以胶东金矿大省为例
影响因子：
8.9
作者：
Yang LQ;Deng J;Guo RP;Guo LN;Wang ZL;Chen BH;Wang XD
通讯作者：
Wang XD
华北克拉通东南部岩石圈地幔与俯冲相关的交代作用：苏鲁造山带北部镁铁质岩脉到中间岩脉的证据
影响因子：
2.9
作者：
M. Santosh;Fang-Fang Hu;Kui-Feng Yang;Zhaochu Hu
通讯作者：
Zhaochu Hu
影响因子：
6.1
作者：
Guochun Zhao;M. Zhai
通讯作者：
Guochun Zhao;M. Zhai