The analysis of geology, petrography, major and trace elements, zircon Hf isotop data of Weihe granites batholith in northern Zhangguangcai range shows that the batholith is composed mainly of granodiorite, ada-mellite, orthoclase and aklali-feldspar granite with a few quartz diorite and tonalite. Intrusive contact relationship has been recognized among different rock types. Geochemical analysis shows that the granites are rich in silicon and potassium contents, belonging to quasi-aluminous and weakly peraluminous rocks ( A/CNK =0. 97 ~ 1. 03). The alkaline (K20 + Na20) is 6.56% ~ 9. 10% in contents, ascribed to high-K calc-alkaline series I-type granite. Rare and trace earth elements of the granites are rich in LREE , Rb, Th, U, K, Hf and depleted in Nb, Ta, P, Ti. Chondrite-normalized REE display moderate negative to slight positive Eu anomalies. Variable zircon Hf i-sotope composition (∈HF (t) = ( -6. 68 ~ +12. 13, TDM2 =464 ~ 1 675 Ma) shows that the magma origrinated from the basic crusts which accreted from depleted mantle during the Phanarozoic and Neoproterozoic, and assimilated older crust locally.%张广才岭北部苇河花岗岩基的地质学、岩相学、全岩主量和微量及锆石Hf同位素的详细解析显示:苇河花岗岩基主体岩性为花岗闪长岩、二长花岗岩、正长-碱长花岗岩及少量的石英闪长岩和英云闪长岩,不同岩石类型之间呈侵入接触关系.岩石富硅富铝,为准铝质-弱过铝质岩石(A/CNK=0.97 ～1.03),全碱(K2O+ Na2O)含量为6.56％ ～9.10％,主要为高钾钙碱性系列Ⅰ型花岗岩.稀土和微量元素组成上,均富集LREE、Rb、Th、U、K、Hf,相对亏损Nb、Ta、P、Ti,δEu从中等程度负异常到弱正异常.不均匀的锆石Hf同位素成分(εHf(t)=(-6.68 ～+12.13),TDM2=464～1657 Ma)表明,岩浆主体来源于显生宙-新元古代时期从亏损地幔中增生的基性下地壳物质,局部同化了更古老的地壳物质.
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