Deep-seated crustal xenoliths record multiple Paleoproterozoic tectonothermal events in the northern North China Craton
Deep-seated crustal xenoliths record multiple Paleoproterozoic tectonothermal events in the northern North China Craton
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华北克拉通北部深部地壳捕虏体记录了多次古元古代构造热事件
DOI：
10.1016/j.precamres.2015.09.021
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发表时间：
2015-11
影响因子：
3.8
通讯作者：
Huang Yan
中科院分区：
文献类型：
--
作者：
Ping Xianquan;Ping Xianquan;Huang Yan;Huang Yan
华北克拉通（NCC）前寒武纪构造演化和地壳增生长期以来一直存在争议。淮安杂岩位于华北克拉通不同构造模式的交汇区，无疑可以为克拉通的构造细分和地壳演化提供一些关键约束。在这里，我们报告了五种深部地壳捕虏体的锆石 U-Pb 年龄和 Hf 同位素，包括一种长英质麻粒岩、一种黑云母-斜长片麻岩、一种角闪石-斜长片麻岩和两种角闪岩。捕虏体首先在淮安杂岩附近的南高崖地区的新生代玄武岩中发现。这些捕虏体中的锆石表明角闪石-斜长片麻岩的原岩年龄为 2459 ± 71 Ma，并且通常记录了 ∼2060、∼1950 和 ∼1850 Ma 的三个构造热事件。 ～2060 Ma 事件由长英质麻粒岩 (2063 ± 22 Ma)、角闪石-斜长片麻岩 (2046 ± 56 Ma) 和角闪岩 (2049 ± 45 Ma) 记录。 ∼1950 Ma 事件的锆石来自长英质麻粒岩 (1951 ± 22 Ma)、黑云母斜长片麻岩 (1950 ± 23 Ma)、角闪石-斜长片麻岩 (1963 ± 56 Ma) 和两种角闪岩 (1976 ± 33 Ma 和1955 ± 28 Ma）。 ～1850 Ma 事件在锆石群中被识别，长英质麻粒岩的年龄为 1868 ± 22 Ma，黑云斜长片麻岩的年龄为 1846 ± 24 Ma，两个角闪岩捕虏体的年龄为 1866 ± 34 Ma 和 1840 ± 54 Ma。结合已发表的数据，推测~2060Ma事件可能对应于古代海洋的俯冲阶段； ∼1950 Ma事件记录了孔兹岩带沿线的阴山地块和鄂尔多斯地块之间的碰撞； ∼1850Ma事件标志着克拉通内沿跨华北造山带的东部和西部地块的最终碰撞。因此，这些深部地壳捕虏体记录了孔兹岩带和 TNCO 的古元古代构造热演化。此外，锆石Hf同位素表明，长英质麻粒岩和黑云斜长片麻岩的原岩源自~2.7 Ga新生地壳的部分熔融；而角闪石则起源于 2.2–2.1 Ga 地幔岩浆，这是世界上许多克拉通的岩浆静止期。因此，华北克拉通北部的淮安杂岩在~2.7 Ga和2.2-2.1 Ga至少经历了两次陆壳生长，其中后者比之前估计的更为显着。
The Precambrian tectonic evolution and crustal accretion in the North China Craton (NCC) have long been matters of debate. The Huai’an Complex, situated at the conjunction area for different tectonic models of the NCC, undoubtedly can provide some key constraints on the tectonic subdivision and crustal evolution of the craton. Here, we report zircon U–Pb ages and Hf-isotope for five deep-seated crustal xenoliths including one felsic granulite, one biotite–plagioclase gneiss, one hornblende–plagioclase gneiss and two hornblendites. The xenoliths were first found in the Cenozoic basalts in the Nangaoya area nearby the Huai’an Complex. The zircons from these xenoliths suggest a protolith age of 2459 ± 71 Ma for the hornblende–plagioclase gneiss, and generally record three periods of ∼2060, ∼1950 and ∼1850 Ma tectonothermal events. The ∼2060 Ma event is recorded by the felsic granulite (2063 ± 22 Ma), hornblende–plagioclase gneiss (2046 ± 56 Ma), and hornblendite (2049 ± 45 Ma). The ∼1950 Ma event is represented in zircons from the felsic granulite (1951 ± 22 Ma), biotite–plagioclase gneiss (1950 ± 23 Ma), hornblende–plagioclase gneiss (1963 ± 56 Ma), and two hornblendites (1976 ± 33 Ma and 1955 ± 28 Ma). The ∼1850 Ma event is recognized in zircon populations with ages of 1868 ± 22 Ma for the felsic granulite, 1846 ± 24 Ma for the biotite–plagioclase gneiss, 1866 ± 34 Ma and 1840 ± 54 Ma for two hornblendite xenoliths. Combined with published data, it is suggested that the ∼2060 Ma event may correspond to the subduction stage of an ancient ocean; the ∼1950 Ma event records the collision between the Yinshan and Ordos Blocks along the Khondalite Belt; and the ∼1850 Ma event marks the final collision of the Eastern and Western Blocks along the Trans-North China Orogen within the craton. Thus, these deep-seated crustal xenoliths recorded the Paleoproterozoic tectonothermal evolution for both the Khondalite Belt and TNCO. In addition, zircon Hf isotopes show that the protoliths of the felsic granulite and biotite–plagioclase gneiss were derived from partial melting of ∼2.7 Ga juvenile crust; whereas the hornblendites originated from 2.2–2.1 Ga mantle magmas, a period of magmatic quiescence in many cratons of the world. Therefore, the Huai’an Complex in the northern NCC witnessed at least two episodes of continental-crust growth at ∼2.7 Ga and at 2.2–2.1 Ga, with the latter more significant than estimated previously.
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影响因子：
3.5
作者：
Neng Jiang;R. Carlson;Jinhui Guo
通讯作者：
Neng Jiang;R. Carlson;Jinhui Guo
影响因子：
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作者：
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影响因子：
1.8
作者：
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通讯作者：
S. Z. Li;Guochun Zhao;M. Santosh;X. Liu;L. Dai
古元古代吕梁杂岩变质火山岩地球化学、U-Pb锆石年龄及其对华北造山带、华北克拉通演化的制约
影响因子：
3.8
作者：
通讯作者：
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影响因子：
3.8
作者：
Guochun Zhao;Peter A. Cawood;San-zhong Li;S. Wilde;M. Sun;Jian Zhang;Yanhong He;C. Yin
通讯作者：
Guochun Zhao;Peter A. Cawood;San-zhong Li;S. Wilde;M. Sun;Jian Zhang;Yanhong He;C. Yin