The Great Xing'an Range has always been a research hotspot in the field of geology.However,there is a relative lack of research on the Mesozoic intermediate igneous rocks in this area remains,with a lack of precise chronological and isotopic da-ta.In this article,the authors conducts systematic study on zircon U-Pb dating and Hf isotopic characteristics of diorite porphy-rite in the Fukeshan area,the northern segment of the Great Xing'an Range,aiming to reveal the diagenetic age and magma source properties of the Fukeshan diorite porphyrite.LA-ICP-MS zircon U-Pb dating results show that the weighted average age of the zircon is(143.3±1.2)Ma(MSWD=0.28),corresponding to the Early Cretaceous.Combined with previous re-search,the authors conclude that there were at least three periods of magmatic intrusion in the Fukeshan area,occurring during the Early Jurassic,Late Jurassic,and early stages of the Early Cretaceous.Zircon Hf isotope tests on the Fukeshan diorite por-phyrite reveal that the zircon εHf(t)values range from-0.86 to+1.26,with two-stage model ages(TDM2)ranging from 1 251-1 117 Ma.Based on previous research results,the magma source area of diorite porphyrite is discussed,and it is be-lieved that the magma originated from the mantle.The mother magma of diorite porphyrite was contaminated by crustal materials during its ascent.
关键词
大兴安岭北段/锆石U-Pb定年/Hf同位素/闪长玢岩/岩浆源区
Key words
Northern segment of the Great Xing'an Range/zircon U-Pb dating/Hf isotope/diorite porphyrite/magma source area
维普
万方数据