地质通报2026，Vol.45Issue(4)：720-739,20.DOI:10.12097/gbc.2023.06.023
北山造山带北部晚古生代岩浆记录及其对百合山洋演化的约束
Late Paleozoic magmatic records from northern Beishan orogenic belt and their constraints on the evolution of the Baiheshan Ocean
摘要
Abstract
[Objective]This study aims to clarify the nature of the mantle source and the magmatic record during the evolution of the Baiheshan Ocean in the north Beishan Orogenic Belt,thereby providing key evidence for understanding the evolution mechanism of accretionary orogens.[Methods]This paper presents systematic zircon U-Pb dating,whole-rock major and trace element,and Sr-Nd-Hf isotopic analyses of newly identified intrusive rocks in the Hongliuxia area.[Results]This work has identified a new set of sillite intruded at 320±3 Ma in the Hongliuxia area of the southern ophiolitic melange belt,which is the product of the major subduction of the Baiheshan Ocean.The sillite shows high-K calc-alkaline geochemical characteristic and was enriched in large-ion lithophile elements like Rb,Th,U,Sr and light rare earth elements and depleted in high field strength elements like Nb,Ta,Ti,showing characteristics of arc magmatic rocks.The values of εNd(t)and εHf(t)of the sillite range from 3.09 to 4.29 and 5.8 to 12.3 respectively,implying that the magma originated from depleted mantle.It may be the product of partial melting of garnet dipyroperidotite constrained by Yb,La and Sm elements.The primary magma underwent limited fractional crystallization and various degrees of crustal contamination.The Early Permian magmatism represents the tectono-magmatic event at the end of the subduction of Baiheshan Ocean.In this work,the widely distributed porphyritic monzogranite was intruded at 275.6±1.4 Ma,belonging to high-K calc-alkaline I-type grantie.They are enriched in large-ion lithophile elements like Rb,Th,U and light rare earth elements and depleted in high field strength elements like Nb,Ti.The values of εHf(t)and TDM2of the porphyritic monzogranite vary from 9.1 to 14.6 and 368 to 719 respectively,implying magma originated from partial melting of the juvenile crust from Neoproterozoic to Paleozoic.[Conclusions]Combined with regional geological material,the accretionary orogeny in the northern part of the Beishan orogenic belt should have ended in the early to middle Permian.关键词
辉绿玢岩/晚古生代/地球化学/Sr-Nd-Hf同位素/北山造山带Key words
sillite/Late Paleozoic/geochemistry/Sr-Nd-Hf isotope/Beishan orogenic belt分类
天文与地球科学引用本文复制引用
张国震,辛后田,田健,刘晨成,牛文超,王明明,段连峰..北山造山带北部晚古生代岩浆记录及其对百合山洋演化的约束[J].地质通报,2026,45(4):720-739,20.基金项目
地球深部探测与矿产资源勘查国家科技重大专项(编号:2025ZD1005705),中国地质调查局项目《燕山-太行成矿带中条山地区铜钴矿产地质调查》(编号:DD20230272)、《华北地区区域基础地质调查》(编号:DD20211339) Supported by Deep Earth probe and Mineral Resources Exploration-National Science and Technology Major Project(No.2025ZD1005705),and the projects of China Geological Survey(Nos.DD20230272,DD20211339) （编号:2025ZD1005705）
