The SHRIMP U-Pb ages for the zircons from the meta-intermediate-basic intrusive rocks cutting the Late Paleoproterozoic Jinshan Croup in eastern Shandong Province, North China Craton are reported. The Jinshan Group is mainly composed of graphite-bearing meta-detrital sediment, meta-calc-silicate rock and marble with upper amphibolite-granulite facies metamorphism and is one portion of khondalite series widely distributed in the North China Craton. Meta-diorite with greenschist-facies metamorphism (SO835 ) has magmatic zircons with a 207Pb/206Pb weighted mean age of 1852 ± 9Ma ( MSWD = 2. 1), Meta-gabbro ( S0816) has mineral association of amphibolite facies metamorphism, but zircons from this rock show fir-texture which is considered to be a feature of zircons formed under granulite facies metamorphism. The metamorphic zircons have a 207Pb/206Pb weighted mean age of 1865 ± 11 Ma (MSWD = 0. 76). Combined with regional data obtained earlier, some conclusions can be drawn as follows: (1) new zircon dating further supports that the Jingshan Croup was formed during the Late Paleoproterozoic; (2) in the eastern Shandong Province, the time from compression to extension was before 1. 87Ga during the Paleoproterozoic. This is similar to the Daqingshan and Hengshan areas, western North China Craton, where the extension is considered to start at 1. 95 ～ 1. 92 Ga in terms of zircon dating of meta-basic dykes and ultra-high temperature metamorphic rocks.%胶东地区的荆山群呈近东西向环绕太古宙TTG花岗质片麻岩展布,主要由成熟度高的含石墨变泥砂质岩石、钙硅酸岩和大理岩组成,变质程度达高角闪岩相-麻粒岩相,具孔兹岩系性质.变质中-基性岩侵入到荆山群.它们的侵位时代对于探讨华北克拉通东部元古宙构造演化以及对荆山群沉积时代的制约,都有重要意义.锆石SHRIMP U-Pb定年结果表明,遭受低级变质的闪长岩( S0835)岩浆锆石年龄为1852±9Ma( MSWD=2.1),遭受中高级变质的辉长岩(S0816)变质锆石年龄为1865±11Ma( MSWD=0.76).结合区域资料,可得出如下结论:(1)荆山群孔兹岩系形成于古元古代晚期(2.2～1.9Ga)；(2)古元古代期间,胶东地区从挤压体制转入伸展体制的时间在1.87Ga之前.在华北克拉通中西部的恒山、大青山地区,存在1.97～1.92Ga辉长岩,在1.92～1.83Ga期间发生变质,与本文研究结果类似.这表明华北克拉通中-西部和东部具有类似的古元古代演化历史.
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