scholarly journals Supplemental Material: Kinematics and structural evolution of the Anziling dome-and-keel architecture in east China: Evidence of Neoarchean vertical tectonism in the North China Craton

2021 ◽  
Author(s):  
Chen Zhao ◽  
Jian Zhang ◽  
et al.
Keyword(s):  
North China Craton ◽  
North China ◽  
Structural Evolution ◽  
East China ◽  
The North

Table S1: U-Pb data of zircons for the samples from the Anziling area.

scholarly journals Kinematics and structural evolution of the Anziling dome-and-keel architecture in east China: Evidence of Neoarchean vertical tectonism in the North China Craton

2021 ◽  
Author(s):  
Chen Zhao ◽  
Jian Zhang ◽  
Guochun Zhao ◽  
Changqing Yin ◽  
Guokai Chen ◽  
...  
Keyword(s):  
Shear Zone ◽  
North China Craton ◽  
Plate Tectonics ◽  
North China ◽  
Structural Evolution ◽  
East China ◽  
Upward Movement ◽  
The North ◽  
Continental Block ◽  
Shear Sense

The debate on the role of vertical versus horizontal tectonism in Archean cratons is intimately linked to the initiation of plate tectonics. The dome-and-keel architecture has been considered as a consequence of vertical tectonism. Although such a structural pattern is documented in some Mesoarchean and older cratons, such as the Kaapvaal and Pilbara cratons, whether it also occurs in Neoarchean cratons is poorly constrained. Determining the kinematics, structural evolution, and the timing of these structures is crucial in understanding how the tectonic behavior operated during the evolution of the early Earth. The North China Craton, especially its eastern part, is a Neoarchean continental block and preserves typical greenstone-granite rock assemblages. Detailed structural mapping reveals that the Anziling area (east China) is characterized by a typical dome structure without significant reworking by later deformation. The dome is in tectonic contact with a supracrustal rock assemblage that is now the dip-slip Shuangshanzi ductile shear zone. In the supracrustal rocks, compositional layers are folded into upright isoclinal folds. Meanwhile, along the shear zone, foliation varies from NNW to SW with sub-vertical dip. Mineral stretching lineations indicate a sinistral shear sense with a slightly oblique-slip component in the north, but show NWW-directed and SW-directed steep dip-slip shear in the west and south, respectively. Kinematic indicators imply that the granitic dome formed through a vertically upward movement accompanied by an uneven clockwise rotation. The supracrustal rocks sank downwards to form the regional keel structure. Structural data suggests that the Anziling area is a typical dome-and-keel structure. U-Pb zircon dating on pre-, syn-, and post-tectonic dykes indicate that the dome-and-keel structure formed at 2530−2500 Ma, and was intimately related to the emplacement of tonalite-trondhjemite-granodiorite granitoids. New data from this study suggest that until the late Neoarchean, the vertical tectonism was still a dominant tectonic regime that was operating in the eastern North China Craton.

scholarly journals Lithospheric Architecture and Metallogenesis in Liaodong Peninsula, North China Craton: Insights from Zircon Hf-Nd Isotope Mapping

Minerals ◽  
2019 ◽  
Vol 9 (3) ◽  
pp. 179 ◽  
Author(s):  
Zhichao Zhang ◽  
Yuwang Wang ◽  
Dedong Li ◽  
Chunkit Lai
Keyword(s):  
North China Craton ◽  
Lower Crust ◽  
North China ◽  
Structural Evolution ◽  
Northern China ◽  
Gold Deposits ◽  
Nd Isotope ◽  
Isotopic Signatures ◽  
The North ◽  
Liaodong Peninsula

The Liaodong Peninsula is an important mineral province in northern China. Elucidating its lithospheric architecture and structural evolution is important for gold metallogenic research and exploration in the region. In this study, Hf-Nd isotope maps from magmatic rocks are constructed and compared to geological maps to correlate isotopic signatures with geological features. It is found that gold deposits of different age periods in Liaodong are located in areas with specific εHf(t) and εNd ranges (Triassic: from −8 to −4 and from −12 to −8, Jurassic: from −22 to −8 and from −14 to −8, Cretaceous: from −12 to −10 and from −22 to −20), respectively. This may reflect that when the Paleo-Pacific plate was subducted beneath the North China Craton, the magma was derived from the juvenile lower crust and the ancient lower crust, and formed the low-to-moderate hydrothermal Au-(Ag) and Pb-Zn deposits in the Triassic. In the Jurassic, continued subduction may have led to lithospheric thickening. Subsequently, the magma from the ancient lower crust upwelled and formed low-to-moderate hydrothermal Au deposits and porphyry Mo deposits. In the Cretaceous, crustal delamination may have taken place. The magma from the ancient lower crust upwelled and formed various low-to-moderate hydrothermal Au deposits.

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