Paleoproterozoic Plate Tectonics Recorded in the Northern Margin Orogen, North China Craton
Paleoproterozoic Plate Tectonics Recorded in the Northern Margin Orogen, North China Craton
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华北北方陆缘造山带古元古代板块构造记录
DOI：
10.1029/2022gc010662
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发表时间：
2022-11
期刊：
影响因子：
3.7
通讯作者：
Chen Wu;Guosheng Wang;Zhiguang Zhou;P. Haproff;A. Zuza;Wenyou Liu
中科院分区：
文献类型：
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作者：
Chen Wu;Guosheng Wang;Zhiguang Zhou;P. Haproff;A. Zuza;Wenyou Liu
古元古代地球板块构造过程的发生得到了地球物理学的支持。与哥伦比亚-努纳超大陆组合有关的2.2-1.8 Ga俯冲-碰撞造山带。随后的超大陆分裂是全球性的证据。1.8-1.6 Ga大火成岩省。华北克拉通是著名的包含古元古代造山带沿着其边缘，在这里被称为北方边缘造山带，但这些造山带的性质和时间的造山和伸展过程及其在超大陆旋回中的作用仍然不清楚。在这篇文章中，我们提出了新的野外观察，U-Pb锆石和斜锆石年代学数据，以及来自华北克拉通北方边缘的主要/微量元素和同位素地球化学分析，详细描述了其古元古代构造和岩浆历史。具体地说，我们记录了ca的发生。2.2-2.0 Ga岩浆弧岩，约。1.9- 1.88Ga构造混杂岩和糜棱岩剪切带，下古元古代褶皱地层。这些岩石受到钙的影响。1.9-1.8 Ga麻粒岩相变质作用和约1.87-1.78 Ga后碰撞，沿着北陆北缘伸展相关的岩浆活动。我们认为这些岩石的形成和就位以及变质和岩浆作用的耦合作用与古元古代洋壳俯冲和随后的陆-陆碰撞作用有关。CA的发生。1.77-1.73 Ga基性岩墙和约. 1.75华北克拉通北方边缘沿着的Ga糜棱岩剪切带可能与区域地幔柱事件有关。我们的研究结果与古元古代的现代板块构造，包括与大洋俯冲有关的板块会聚和大陆-大陆碰撞是一致的。
The occurrence of plate tectonic processes on Earth during the Paleoproterozoic is supported by ca. 2.2–1.8 Ga subduction‐collision orogens associated with the assembly of the Columbia‐Nuna supercontinent. Subsequent supercontinent breakup is evidence by global ca. 1.8–1.6 Ga large igneous provinces. The North China craton is notable for containing Paleoproterozoic orogens along its margins, herein named the Northern Margin orogen, yet the nature and timing of orogenic and extensional processes of these orogens and their role in the supercontinent cycle remain unclear. In this contribution, we present new field observations, U‐Pb zircon and baddeleyite geochronology dates, and major/trace‐element and isotope geochemical analyses from the northern margin of the North China craton that detail its Paleoproterozoic tectonic and magmatic history. Specifically, we record the occurrence of ca. 2.2–2.0 Ga magmatic arc rocks, ca. 1.9–1.88 Ga tectonic mélange and mylonitic shear zones, and folded lower Paleoproterozoic strata. These rocks were affected by ca. 1.9–1.8 Ga granulite‐facies metamorphism and ca. 1.87–1.78 Ga post‐collisional, extension‐related magmatism along the cratonal northern margin. We interpret that the generation and emplacement of these rocks, and the coupled metamorphic and magmatic processes, were related to oceanic subduction and subsequent continent‐continent collision during the Paleoproterozoic. The occurrence of ca. 1.77–1.73 Ga mafic dykes and ca. 1.75 Ga mylonitic shear zones along the northern margin of the North China craton may have been related to a regional mantle plume event. Our results are consistent with modern style plate tectonics, including oceanic subduction‐related plate convergence and continent‐continent collision, operating in the Paleoproterozoic.