Petrogenesis of the Archean tonalite–trondhjemite–granodiorite (TTG) and granites in the Lushan area, southern margin of the North China Craton: Implications for crustal accretion and transformation

Geochemistry, geochronology, and geodynamic implications of mafic‐felsic dykes from the Hadamengou area, north‐western North China Craton

“…During the Late Neoarchean (2.6–2.5 Ga), the seven micro‐blocks within the NCC began to amalgamate through oceanic subduction and continent‐continent collisions (Figure 1b; Tang & Santosh, 2018; Wan et al, 2015; Zhai, Bian, & Zhao, 2000; Zhai et al, 2005; Zhai, 2014). The NCC underwent extensive tectono‐thermal events during the amalgamation process and generated abundant intrusive rocks in the NCC, including tonalite‐trondhjemite‐granodiorite (TTG), associated with minor gabbroic and dioritic rocks (Gong, Zhang, Yu, Li, & Hou, 2012; Wan et al, 2015, 2017; Wang et al, 2017; Zhai, 2014; Zhou, Zhao, Zhai, Gao, & Sun, 2014). Previous studies identified that widespread magmatic rocks of the Late Neoarchean are distributed in the Jining Block, especially the Daqingshan region and adjacent Guyang area.…”

Late Mesoarchean crust growth event: evidence from the ca. 2.8 Ga granodioritic gneisses of the Xiaoqinling area, southern North China Craton

“…Three spots (31,32,33) analyzed on metamorphic rims have Th and U contents varying from 65 to 79 and 1033-1122 ppm, respectively, with Th/U ratios of 0.06-0.07, which indicates a metamorphic origin. The 207 Pb/ 206 Pb ages of these three spots vary from 1919 ± 12 to 1946 ± 12 Ma, indicating a Paleoproterozoic metamorphic event.…”

“…The relatively weak fractionated REE pattern, indicating that the partial melting of hydrated basaltic rocks only left less amounts of garnet in the residue [55]. These rocks have relative low Dy/Yb ratios (1.87-2.32) and Gd/Yb ratios (2.14-3.00), suggestive of amphibole in the residue during partial melting [32,56,57]. The negative Eu anomalies with low Sr contents suggest plagioclase in the residue or relatively strong differentiation [55,58,59].…”

“…Because of the well development of ca. 2.8 Ga magmatic event [18,[29][30][31][32], geological investigation in the Lushan area of the Taihua Complex has achieved great progress. Previously, Kröner et al [29] and Sun et al [30] delineated tonalite gneiss in this area with evaporation 207 Pb/ 206 Pb zircon ages of 2841 ± 16 and 2806 ± 7 Ma, respectively.…”

“…In this study, Mesoarchean (ca. 2.8 Ga) TTG rocks from Taihua Complex was firstly recognized in the Xiaoqinling area, which previously had only been recognized in Lushan [18,[29][30][31][32]. Based on petrography, geochemical analysis and zircon U-Pb-Hf isotopic analysis, we discuss the geochronology, petrogenesis of the rocks as well as the Archean crustal growth and evolution of the crystalline basement, that further bring insight in understanding the Precambrian crustal evolution of the NCC.…”