High-temperature S-type granitoids (charnockites) in the Jining complex, North China Craton: Restite entrainment and hybridization with mafic magma
High-temperature S-type granitoids (charnockites) in the Jining complex, North China Craton: Restite entrainment and hybridization with mafic magma
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华北克拉通济宁杂岩中高温S型花岗岩（镁铁岩）：复位铁矿的夹带及其与镁铁质岩浆的杂化
DOI：
10.1016/j.lithos.2018.09.035
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发表时间：
2018-11
期刊：
影响因子：
3.5
通讯作者：
Qian JiaHui
中科院分区：
文献类型：
--
作者：
Wang LuoJuan;Guo JingHui;Yin Changqing;Peng Peng;Zhang Jian;Spencer Christopher J.;Qian JiaHui
凉城石榴石花岗岩类是产于中国克拉通北部孔达尔岩带东段济宁超高温杂岩麻粒岩相变质岩中的偏地S型花岗岩。这些石榴石花岗岩中含有镁铁质微粒包体，并与许武家辉长花岗岩的众多小侵入体密切相关，表现出岩浆混合和混合结构。石榴石花岗岩类的典型矿物学特征为斜长石+钾长石+石英+石榴石+黑云母+斜方辉石。单键铅离子探针测年表明，石榴石花岗岩类及其伴生的辉长闪长岩与超高温变质作用的年龄在1.93~1.92 之间，并记录到了缓慢冷却过程中的1.92 Ga变质作用。与典型的S型花岗岩相比，石榴石花岗岩具有斜方辉石的存在，高的石榴石(高达25%)和强过铝(AsI = 1.11~1.55)，低的SiO_2(57.8~70.1 wt%)和高的FeO+ (5.6~14.4 wt%)的特征。矿物化学(高钛黑云母和高铝斜方辉石)、高铝斜方辉石温度(910~989 °C)和高的锆饱和温度(82 5~90 1 °C)和低的全岩Al_2O_3/TiO_2比值(11~28)，表明石榴石花岗岩类来自超高温麻粒岩相条件下变质沉积岩的黑云母脱水熔融。结构和成分证据表明，凉城石榴石花岗岩中有相当大比例的石榴石可能是源区夹带的包晶相。石榴石集合体也可能代表夹带的富含石榴石的残留物。石榴石花岗岩的大HREE变化也支持富含石榴石残岩的夹带。石榴石花岗岩类与镁铁质包体和辉长岩的大多数主要元素呈近线性趋势，表明镁铁质岩浆参与了花岗岩类的成岩作用。石榴石花岗岩中锆石的εHf(T)值(−1.0 − +5.6)和δ18O值(9.2~11.6‰)与辉长闪长岩中的部分重叠(εHf(T)= −2.9 − +3.5，δ18O = 7.7~10.9‰)，表明它们之间存在强烈的相互作用和混合作用。主元素模拟表明，在深熔熔体中加入20-40%的钙辉石(石榴石)和辉长闪长岩是造成化学变化较大的原因。因此，凉城石榴石花岗岩代表了高温(>；900 °C)、H2O不饱和、强过铝的花岗岩类，是变质沉积岩大规模熔融和富RESite深熔熔体与镁铁质岩浆混合的产物。济宁杂岩中大量的高温花岗岩与超高温麻粒岩组合，显示了花岗质下地壳对镁铁质底侵的热响应。
The Liangcheng garnet granitoids are parautochthonous S-type granites that occur within granulite-facies metasediments in the ultrahigh-temperature (UHT) Jining Complex, eastern part of the Khondalite Belt, North China Craton. These garnet granitoids contain mafic microgranular enclaves and are intimately associated with numerous small intrusions of the Xuwujia gabbronorites, showing magma mingling and mixing textures. Typical mineralogy in the garnet granitoids is plagioclase + K-feldspar + quartz + garnet + biotite ± orthopyroxene. Usingle bondPb ion microprobe dating of zircon suggests that garnet granitoids and associated gabbronorites were coeval with UHT metamorphism at ~1.93–1.92 Ga, and also recorded ~1.92 Ga metamorphism during slow cooling. Garnet granitoids are characterized by the presence of orthopyroxene, high modal proportion of garnet (up to 25%) and strongly peraluminous (ASI = 1.11–1.55) along with lower SiO2(57.8–70.1 wt%) and higher FeOt+ MgO (5.6–14.4 wt%) contents than typical S-type granites. Mineral chemistry (high Ti biotite and high Al orthopyroxene), high Al-in-orthopyroxene temperature (910–989 °C) and Zr saturation temperature (825–901 °C), and low whole-rock Al2O3/TiO2ratios (11–28), indicate that garnet granitoids were derived from biotite dehydration melting of metasedimentary rocks under UHT granulite-facies conditions. Textural and compositional evidence suggests that a significant proportion of garnets in the Liangcheng garnet granitoids are potentially a peritectic phase entrained from the source. Garnet aggregates may also represent entrained garnet-rich restites. The large HREE variations of garnet granitoids also support the entrainment of garnet-rich restites. Garnet granitoids display nearly linear trends with the mafic enclaves and gabbronorite for most major elements that demonstrates the involvement of mafic magma in the granitoid petrogenesis. The εHf(t)values (−1.0 − +5.6) and δ18O values (9.2–11.6‰) of zircons in garnet granitoids partly overlap with those in gabbronorites (εHf(t)= −2.9 − +3.5, δ18O = 7.7–10.9‰), suggesting the strong interaction and mixing process between them. Major element modelling suggests that the addition of 20–40% restites (garnetites) and gabbronorites to the anatectic melts was responsible for the large chemical variations. Therefore, the Liangcheng garnet granitoids represent high-temperature (> 900 °C), H2O-undersaturated, strongly peraluminous granitoids, and are produced by large-scale melting of metasedimentary rocks and subsequent mixing between restite-rich anatectic melt and mafic magma. The voluminous high-temperature granitoids, coupled with UHT granulites in the Jining Complex, manifest the thermal response of a granulitic lower crust to the mafic underplating.
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影响因子：
64.8
作者：
Charles E. Lesher
通讯作者：
Charles E. Lesher
影响因子：
3.5
作者：
Shoujie Liu;T. Tsunogae;Wenshan Li;Hisako Shimizu;M. Santosh;Y. Wan;Jianghai Li
通讯作者：
Shoujie Liu;T. Tsunogae;Wenshan Li;Hisako Shimizu;M. Santosh;Y. Wan;Jianghai Li
影响因子：
5.8
作者：
A. Kemp;T. Shimura;C. Hawkesworth;Eimf
通讯作者：
A. Kemp;T. Shimura;C. Hawkesworth;Eimf
影响因子：
3.5
作者：
D. Vielzeuf;J. Holloway
通讯作者：
D. Vielzeuf;J. Holloway
DOI：
10.1007/978-94-015-9050-1_2
发表时间：
1998
期刊：
--
影响因子：
--
作者：
A. Douce;T. C. McCarthy
通讯作者：
A. Douce;T. C. McCarthy