Petrogenesis and tectonic setting of Neoarchean K-rich granitoids in the Zhulagou area: Implications for the crustal maturation of Yinshan Block, western North China Craton

作者：Xiao Wang, Jin Liu, Hai Zhou, Xiaoguang Liu, Chenying Yu, Shuhui Zhang, Jian Zhang · 发表于：Geosystems and Geoenvironment · 年份：2025 · DOI：10.1016/j.geogeo.2025.100384 · 被引用次数：5 · 研究领域：Geological and Geochemical Analysis、Geochemistry and Geologic Mapping、High-pressure geophysics and materials

• Emplacement of the Zhulagou K-rich granitoids occurred at 2.52–2.50 Ga. • Zhulagou K-rich granitoids from the partial melting of a thickened lower crust. • Partial melting of the lower crust triggered by Neoarchean mantle plume activity. K-rich granitoids are considered as an indicator of the maturation of the continental crust, particularly in correlation to the significant crustal evolution during the Neoarchean Eon. The Yinshan Block, a typical Neoarchean microcontinental block of the western North China Craton (NCC), preserves several typical K-rich granites (monzogranitic gneisses). However, their petrogenesis and tectonic background of these remain unclear, hindering our understanding of the late Neoarchean crustal evolution of the NCC. This study presents new geochronological, geochemical, and Sr-Nd-Pb-Hf isotopic data on the K-rich granites exposed in the Zhulagou area, a key exposure of the Yinshan Block. Zircon U–Pb dating results suggest that the K-rich granites were emplaced at 2.52–2.50 Ga. The K-rich granites exhibit high SiO 2 (68.70–74.10 wt. %) and K 2 O (3.40–7.79 wt. %) and lower MgO (0.24–1.04 wt. %) content. They also have high Sr/Y and (La/Yb) N ratios, as well as low Y and Yb contents. Furthermore, they display variable ε Hf ( t ) (–1.1 to +2.5) and ε Nd ( t ) (–6.05 to +1.64) values, with relatively low Pb isotopes ( 206 Pb/ 204 Pb (t) = (13.910485–15.241164), 207 Pb/ 204 Pb (t) = (14.806723–15.259938), and 208 Pb/ 204 Pb (t) = (33.758621–35.592727))...