Switch of geodynamic setting from the Paleo-Asian Ocean to the Mongol-Okhotsk Ocean: Evidence from granitoids in the Duobaoshan ore field, Heilongjiang Province, Northeast China
Switch of geodynamic setting from the Paleo-Asian Ocean to the Mongol-Okhotsk Ocean: Evidence from granitoids in the Duobaoshan ore field, Heilongjiang Province, Northeast China
复制标题
古亚洲洋到蒙古-鄂霍茨克洋的地球动力学背景转换——来自黑龙江省多宝山矿田花岗岩类的证据
DOI：
10.1016/j.lithos.2019.04.006
复制
发表时间：
2019-07
期刊：
影响因子：
3.5
通讯作者：
Guangming Li
中科院分区：
文献类型：
--
作者：
Chao Zhao;Kezhang Qin;Guoxue Song;Guangming Li
本文报道了中亚造山带东部多宝山矿田三叠纪花岗岩类锆石U-Pb年龄和全岩地球化学资料。测年结果表明，多宝山矿田三叠纪花岗岩类侵位时间约为2000年。244-223 Ma。这些样品是典型的与俯冲有关的弧岩浆岩，富集大离子亲石元素（LILEs），亏损高场强元素（HFSEs），具有相对较高的Sr（平均1036 ppm）和较低的Y（平均10 ppm）和Yb（平均1 ppm）的含量，表现出埃达克岩的地球化学性质。样品的全岩平均初始~（87）Sr/~（86）Sr比值为0.70394，平均Nd ~（13）Nd（t）、锆石Nd ~（13）Hf（t）和两阶段Hf模式年龄分别为4.62、10.29和766 Ma。这些地球化学特征揭示了一个加厚的下地壳源。对多宝山矿田早古生代、三叠纪和早侏罗世花岗岩类的综合分析表明，这三个阶段的岩浆活动都与年轻的下陆壳物质熔融有关。早古生代是地壳垂直生长的主要时期，形成了幼年下陆壳。三叠纪花岗岩类是由增厚的幼年下地壳部分熔融形成的岩浆源岩，侏罗纪花岗岩类是由拆离的幼年下地壳部分熔融形成的岩浆源岩。地质观测和构造背景分析表明，多宝山矿田中生代古亚洲洋构造体制在蒙古-鄂霍次克洋闭合后转换为蒙古-鄂霍次克洋构造体制。早古生代花岗岩类形成于额尔古纳-兴安复合地块之下的古亚洲洋板块向北西俯冲的俯冲环境。三叠纪花岗岩类形成于与蒙古-鄂霍次克洋向南俯冲有关的超俯冲伸展体制，侏罗纪花岗岩类形成于与蒙古-鄂霍次克洋晚期俯冲有关的板片回滚背景。
This paper presents new zircon U-Pb ages and whole-rock geochemical data for Triassic granitoids in the Duobaoshan ore field, in the eastern Central Asian Orogenic Belt (CAOB). Dating results reveal that the Triassic granitoids in the Duobaoshan ore field were emplaced ca. 244–223 Ma. These samples are typical subduction-related arc magmatic rocks that are enriched with large-ion lithophile elements (LILEs), depleted in high field strength elements (HFSEs), and have relatively high Sr (average 1036 ppm) and low Y (average 10 ppm) and Yb (average 1 ppm) contents that exhibit adakite-like geochemical properties. The samples feature a juvenile whole rock average initial87Sr/86Sr ratio of 0.70394 and an average ɛNd(t), zircon ɛHf(t), and two-stage Hf model age of 4.62, 10.29, and 766 Ma respectively. These geochemical features reveal a thickened lower crust source. Comprehensive analyses of the early Paleozoic, Triassic, and early Jurassic granitoids in the Duobaoshan ore field indicate that the magmatism of these three stages was related to the melting of the juvenile lower continental crust materials. The early Paleozoic was the primary period of vertical crust growth, during which time the juvenile lower continental crust was formed. The Triassic granitoids derived from magma were generated by partial melting of the thickened juvenile lower crust and the Jurassic granitoids derived from the partial melting of the delaminated juvenile lower crust. Geological observation and tectonic setting analyses reveal that the Paleo-Asian Ocean tectonic regime in the Duobaoshan ore field switched to the Mongol-Okhotsk Ocean in the Mesozoic after its closure. The early Paleozoic granitoids were formed in a subduction setting related to the northwestward subducted Paleo-Asian Oceanic slab underlying the Erguna-Xing'an composite block. The Triassic granitoids were formed under a supra-subduction extensional regime related to the southward subduction of the Mongol-Okhotsk Ocean, and the Jurassic granitoids were generated under a slab rollback setting related to the late stage subduction of the Mongol-Okhotsk Ocean.
登录
查看更多内容
蒙古—鄂霍茨克洋板块早中生代向南俯冲历史：来自额尔古纳地块早中生代侵入岩年代学和地球化学的证据
影响因子：
6.1
作者：
Tang Jie;Xu Wenliang;Wang Feng;Zhao Shuo;Wang Wei
通讯作者：
Wang Wei
影响因子：
64.8
作者：
DEFANT, MJ;DRUMMOND, MS
通讯作者：
DRUMMOND, MS
影响因子：
3.5
作者：
C. Stern;R. Kilian
通讯作者：
C. Stern;R. Kilian
影响因子：
6.1
作者：
Yong‐jiang Liu;Weimin Li;Zhiqiang Feng;Quanbo Wen;F. Neubauer;Chenyue Liang
通讯作者：
Yong‐jiang Liu;Weimin Li;Zhiqiang Feng;Quanbo Wen;F. Neubauer;Chenyue Liang
影响因子：
3.3
作者：
Wang Zhitian;Qin Kezhang
通讯作者：
Wang Zhitian;Qin Kezhang