桑干地区大同－集宁一带孔兹岩系分布区有大量早元古代花岗岩发育。依据矿物组成和地质特征，这些花岗岩可分为两种类型：大规模的石榴石花岗岩和小规模的淡色花岗岩。花岗岩中长石Ｐｂ同位素组成显示，石榴石花岗岩是孔兹岩系部分熔融的直接产物，而淡色花岗岩不是孔兹岩系简单的部分熔融产物。石榴石花岗岩中锆石Ｕ－Ｐｂ一致年龄为１８３６±１８Ｍａ，代表石榴石花岗岩的形成年代。淡色花岗岩的锆石Ｕ－Ｐｂ一致线上交点年龄为１９１２±９８Ｍａ，形成略早。孔兹岩系２０７Ｐｂ／２０４Ｐｂ值整体上高于华北麻粒岩下地壳，具有上地壳的Ｐｂ同位素组成特征，其沉积原岩应该来自华北晚太古代形成的大陆地壳。根据深成岩浆作用和变质作用的年代学资料，可以确定桑干地区早元古代如下构造－热事件序列：小基性岩体侵入（２．２～２．３Ｇａ）、早期淡色花岗岩生成（２．１～１．９Ｇａ）、麻粒岩相变质作用、剪切作用和大规模石榴石花岗岩发育（１．８４Ｇａ）、伟晶岩的形成（１．８０Ｇａ）和基性岩墙群的出现（１．７７Ｇａ）。大规模石榴石花岗岩形成于构造－热事件峰期 Sanggan area Datong - Jining area khod rock distribution area has a large number of early Proterozoic granite development. Based on mineralogical composition and geological characteristics, these granites can be divided into two types: large-scale garnet granite and small-scale pastel granite. The isotopic composition of mid-feldspar in granite shows that garnet granite is the direct product of the partial kondalite melting, while the pale-colored granite is not a simple partial melting product of the khondalite series. The uniform zircon U-Pb age of garnet granite is 1836 ± 18Ma, representing the age of garnet granite. The pale-grained zircon U-Pb zircon dating line is 1912 ± 98 Ma, forming slightly earlier. The 207Pb / 204Pb values ​​of the Khondzian series are generally higher than the lower crust of the North China granulite and are characterized by Pb isotopic composition of the upper crust. The sedimentary protolith should come from the continental crust formed in the late Archean of North China. According to the chronological data of the deep magmatism and metamorphism, the following sequence of tectono-thermal events in the Sanggan area can be identified: infiltration of small basic rocks (2.2 ~ 2.3Ga) and formation of early pale granite (2). 1 ~ 1.9Ga), granulite facies metamorphism, shearing and large-scale garnet granite development (1.84Ga), pegmatite formation (1.80Ga) and occurrence of basic dyke swarms (1 .77Ga). Large-scale garnet granite was formed during the tectono-thermal event