岩石矿物学杂志2026，Vol.45Issue(3)：527-550,24.DOI:10.20086/j.cnki.yskw.2026.5086
华北克拉通辽南地块太古宙地壳增生与再造
The Archean crustal growth and reworking in the Liaonan Block,North China Craton:Evidence from U-Pb geochronology and Hf isotopes of zircon from granitoid rocks
摘要
Abstract
Late Neoarchean granitoid gneisses are widely distributed in the Early Precambrian metamorphic base-ment of the Liaonan Block,the North China Craton(NCC),and record important information on the formation and evolution of the continental crust in the Early Precambrian.In this study,we present zircon LA-ICP-MS U-Pb ages,trace element compositions,and Lu-Hf isotopic data from four granitoid gneiss samples collected from the Liaonan Block.Most zircons exhibit oscillatory zoning and high Th/U ratios(0.18～2.21),along with REE pat-terns characterized by depleted LREEs and enriched HREEs,consistent with a magmatic origin.The 207Pb/206Pb weighted mean ages of the four granitoid samples are 2 529±10 Ma(MSWD=0.12,n=14),2 475±27 Ma(MSWD=3.1,n=13),2 502±15 Ma(MSWD=2.7,n=14),and 2 478±8 Ma(MSWD=0.81,n=25),respectively,recording the magmatic events related to crustal differentiation during the late Neoarchean.Zircon Hf isotopic compositions show positive εHf(t)values(+0.11 to+5.29),with two-stage model ages(tDM2)ranging from 2.9 to 2.7 Ga,suggesting the granitoids were derived mainly from partial melting of juvenile crust formed during this period.A few zircons yield negative εHf(t)values(-3.2 to-0.8)and older tDM2 ages of 3.12～2.90 Ga,reflecting the involvement of ancient reworked continental crustal components older than 2.9 Ga.Combi-ning the new results with published zircon Hf isotope data,it has been demonstrated that the Liaonan Block experi-enced major crustal growth during 2.9～2.7 Ga and crustal reworking at 2.5 Ga and 2.47 Ga,which were driven by upwelling mantle.The resulting widespread potassic granitic rocks signify the stabilization and cratonization of the block.关键词
华北克拉通/辽南地块/地壳增生/锆石U-Pb定年/锆石Hf同位素Key words
North China Craton/Liaonan Block/crustal growth/zircon U-Pb dating/zircon Hf isotope分类
天文与地球科学引用本文复制引用
李圆硕,刘建辉,刘福来,丁正江,徐玮男,李胜森..华北克拉通辽南地块太古宙地壳增生与再造[J].岩石矿物学杂志,2026,45(3):527-550,24.基金项目
国家重点研发计划项目(2023YFC2906900) （2023YFC2906900）
地球深部探测与矿产资源勘查国家科技重大专项(2025ZD1005300) （2025ZD1005300）
国家自然科学基金项目(42172218) （42172218）
中国地调局地质调查项目(DD20221646) National Key Research and Development Program of China(2023YFC2906900) （DD20221646）
Deep Earth Probe and Mineral Resources Exploration-National Science and Technology Major Project(2025ZD1005300) （2025ZD1005300）
National Natural Science Foundation of China(42172218) （42172218）
Geological Survey Fund of the China Geological Survey(DD20221646) （DD20221646）
