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对大别山核部九资河花岗岩进行了岩石学、稀土和微量元素地球化学、同位素地球化学研究，讨论了其侵 位特征、成因和构造意义。九资河花岗岩的 ＡＮＫ＝ １． １５～１． ４５（平均１． ２８），ＡＣＮＫ＝０， ９１～１． １０（平均 １． ００）， δＥｕ＝ ０．３６～１．１６，ε_（Ｎｄ）（ｔ）＝－１６．５，ε_（Ｓｒ）（ｔ）＝５９．１。九资河花岗岩体为一沿ＮＥ向剪切带就位的原地．半原地花岗岩体，与 世界典型的原地－半原地深熔花岗岩体相比，九资河花岗岩体具有这些花岗岩体的一般特征：出现于高级变质区， 与围岩呈渐变过渡或侵入关系，岩石属于亚碱性系列的钙碱性岩系，但岩性复杂，具有片麻状或条带状构造，矿物残 留结构发育，围岩无热变质，残留的暗色包体特别多，侵入岩在Ｒｂ－Ｂａ－Ｓｒ图解中成分范围一致，岩浆演化方式为“残 留体模式”。不同点在于九资河花岗岩为偏铝质－过铝质之间的过渡类型，且为Ⅰ型花岗岩，其他的为过铝质Ｓ型花 岗岩。这种差别的原因在于九资河花岗岩的源岩以变质火成岩──ＴＴＧ片麻岩为主，而其他花岗岩的源岩为变质沉 积岩。九资河花岗岩不是“变质或交代”成因，而是由深熔作用形成，源岩中斜长石和黑云母的熔融反应控制了熔融 过程，深熔作用的
Petrological, rare earth and trace element geochemistry and isotope geochemistry of the Jiuzihe granite in the core of the Dabie Mountains were studied, and their emplacement characteristics, genesis and tectonic significance were discussed. Jiuzihe granite ANK = 1. 15 ~ 1. 45 (average 1.28), ACNK = 0, 91 ~ 1. 10 (average 1.00), δEu = 0.36-1.16, ε_ (Nd) (t) = -16.5 and ε_ (Sr) (t) = 59.1. Jiuzihe granite body is a place along the NE shear zone. Semi-situ granite body, compared with the typical in situ-semi-situ deep-water granite body in the world, the Jiuzihe granite body has the general characteristics of these granite bodies: they appear in the advanced metamorphic area and have a gradual transition or intrusion relationship with the surrounding rock, The rocks belong to the alkaline-alkaline series of calc-alkaline rocks, but are lithologically complex with gneiss or strip-like structure. The residual structure of minerals is developed. The surrounding rocks are not thermally deteriorated. The residual dark-colored inclusions are particularly large. The compositions of Rb-Ba-Sr are in the same range and the magmatic evolution mode is “residual body mode”. The difference is that the Jiuzihe granite is a transitional type between the partial aluminum and the peraluminous, and is type I granite, while the others are peraluminous S-type granites. The reason for this difference is that the source rocks of the Jiuzihe granite are dominated by metamorphic igneous -TTG gneiss, while the source rocks of other granites are metamorphic sedimentary rocks. Jiuzihe granite is not a cause of metamorphism or alteration, but is formed by deep-melting. Melting reactions of plagioclase and biotite in source rocks control the melting process, and the deep-melting