The Mesoarchean Tiejiashan-Gongchangling potassic granite in the Anshan-Benxi area, North China Craton: Origin by recycling of Paleo- to Eoarchean crust from U-Pb-Nd-Hf-O isotopic studies
The Mesoarchean Tiejiashan-Gongchangling potassic granite in the Anshan-Benxi area, North China Craton: Origin by recycling of Paleo- to Eoarchean crust from U-Pb-Nd-Hf-O isotopic studies
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华北克拉通鞍山-本溪地区中太古代铁家山-弓长岭钾质花岗岩：U-Pb-Nd-Hf-O同位素研究中古至太太古代地壳的成因
DOI：
10.1016/j.lithos.2017.08.009
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发表时间：
2017-10
期刊：
影响因子：
3.5
通讯作者：
Dunyi Liu
中科院分区：
文献类型：
--
作者：
Chunyan Dong;Yusheng Wan;Hangqiang Xie;Allen P. Nutman;Shiwen Xie;Shoujie Liu;Mingzhu Ma;Dunyi Liu
中太古代和更古老的钾质花岗岩是地球历史早期古陆壳再循环的重要标志。通过全岩、锆石地球化学和年代学的综合研究，确定了华北鞍山-本溪地区中太古代最大的前新太古代花岗岩域-铁家山-弓长岭花岗岩的年龄和源区物质。15个样品的SHRIMP锆石U-Pb定年结果表明，花岗岩的岩浆结晶作用发生在2.95 ~ 3.0Ga之间，并反映了2.91Ga左右的叠加构造事件。花岗岩以高SiO2、K2 O、低CaO、FeOt、MgO、TiO 2为特征，具过铝特征。（La/Yb）比值变化大，Eu、Ba负异常强，Nb、P、Ti亏损。全岩Nd和岩浆锆石Hf同位素组成变化较大，但大多数εNd（t）和εHf（t）值均< 0，tDM（Nd）和tDM（Hf）值分别为3.3 ~ 3.9Ga和3.3 ~ 4.0Ga。岩浆锆石没有很强的铅损失（不一致性≤ 20%），δ 18 O值为+3.14 ~+8.39。部分样品中有3.3- 3.7Ga捕虏晶锆石。花岗岩的形成是古-始新世大陆物质在陆内环境中再循环的结果，几乎没有中太古代地幔源的贡献。其来源可能主要是未改变的古片麻岩，以及尚未确定的受早期低温蚀变影响的古太古代物质（风化岩石或碎屑沉积物）。
Mesoarchean and older potassic granites are important indicators of recycling of ancient continental crust early in Earth's history. This study of integrated whole rock and zircon geochemistry and geochronology reports the age and identification of the source materials of the > 200 km2Mesoarchean Tiejiashan-Gongchangling granite in the Anshan-Benxi area, North China Craton, the largest pre-Neoarchean granite domain in the craton. SHRIMP U-Pb zircon dating on 15 samples indicates the magmatic crystallization of the granites between 2.95 and 3.0 Ga and reveals a superimposed tectonothermal event at ~ 2.91 Ga. The granites are characterized by high SiO2and K2O, low CaO, FeOt, MgO and TiO2with peraluminuous features. They show large variations in (La/Yb)nand strong negative Eu and Ba anomalies and Nb, P and Ti depletions. Whole rock Nd and magmatic zircon Hf isotopic compositions show large variations, but with most having εNd(t) and εHf(t) values < 0, with tDM(Nd) and tDM(Hf) values varying from 3.3 to 3.9 Ga and 3.3 to 4.0 Ga, respectively. Magmatic zircons without very strong lead loss (discordance ≤ 20%) have δ18O values of + 3.14 to + 8.39. 3.3–3.7 Ga xenocrystic zircons occur in some samples. The granite formed as a result of recycling of Paleo- to Eoarchean continental material in an intracontinental environment, with little if any contribution from Mesoarchean mantle sources. The sources could be predominantly unaltered ancient gneisses, together with yet to be identified Paleo- to Eoarchean materials affected by early low temperature alteration (weathered rocks or clastic sediment).
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影响因子：
1.8
作者：
Wan Yu
通讯作者：
Wan Yu
影响因子：
3.5
作者：
D. Vielzeuf;J. Holloway
通讯作者：
D. Vielzeuf;J. Holloway
锆石U-Pb和Hf同位素对华北克拉通鞍山早太古代地壳演化的约束
影响因子：
3.8
作者：
通讯作者：
--
影响因子：
0.8
作者：
A. Masuda
通讯作者：
A. Masuda
影响因子：
5.3
作者：
D. DePaolo
通讯作者：
D. DePaolo