Whether any age records about the assemblage and rifting of the Rodinia supercontinent are preserved in the North China Craton (NCC) like in the South China Craton (SCC) is a key issue to understand the Proterozoic tectonic evolution of the NCC.This study focuses on LA-ICP-MS U-Pb dating of detrital zircons from the Cambrian and Jurassic clastic rocks in Western Hills of Beijing to reveal significant Precambrian,especially Late Paleoproterozoic to Neoproterozoic geological events of the NCC.U-Pb age data of detrital zircons show that age peaks of the detrital zircon grains of the calcareous fine sandstone from the Cambrian Xuzhuang Formation focus on ～ 1.38Ga and ～ 1.14Ga.There are also ～ 1.56Ga,～912Ma,～814Ma,～740Ma,～630Ma and ～507Ma age groups in this sandstone.The age peaks of the detrital zircon grains of the feldspar lithic fine sandstone and the silty mudstone from the Jurrasic Yaopo Formation focus on ～ 2.5Ga,1.88 ～ 1.8Ga,～ 1.74Ga,～ 1.6Ga and 186Ma.Besides,there are ～ 2.77Ga,～ 2.0Ga,～1.2Ga,～488Ma,～256Ma and ～ 233Ma age groups.All the three rocks have low compositional and textural maturity,which indicates nearer provenances.So the detrital material of the three rocks may mainly derive from the interior and the north margin of the NCC,that means,the age groups of the detrital zircons may record significant Precambrian geological events of the NCC.Detrital zircon ages of ～ 2.77Ga,～ 2.5Ga,2.1 ～ 2.0Ga and 1.88 ～ 1.8Ga correspond respectively to Precambrian significant events of crustal growth,cratonization,rifting and orogenesis in the NCC; Detrital zircon ages of ～ 1.74Ga,～ 1.6Ga,～ 1.56Ga,～ 1.38Ga,～ 912Ma and ～814Ma record Late Paleoproterozoic to Neoproterozoic multi rifting events developing after the final cratonization at about 1.8Ga of the NCC.Magmatic and metamorphic rocks corresponding to 1.3 ～ 1.0Ga,～740Ma and ～ 630Ma detrial zircon ages seldom crop out in the NCC,whereas develop broadly in the SCC and may correlate to various stages of assemblage and rifting of the Rodinia supercontinent.Age records of Late Paleoproterozoic to Neoproterozoic geological events of the NCC preserved in detrital zircons from the Phanerozoic clastic rocks in the NCC may provide significant evidences to discuss the geological evolution of the NCC in the Proterozoic and the relationship of the NCC and the SCC.%华北克拉通是否同华南克拉通一样保存有与Rodinia超大陆聚合和裂解有关的年龄记录是理解华北克拉通元古宙构造演化的重要科学问题.本文对位于华北克拉通燕辽裂陷槽的北京西山地区的寒武系和侏罗系碎屑岩进行锆石LA-ICP-MS U-Pb年代学研究,目的是通过碎屑锆石年龄揭示华北克拉通前寒武纪尤其是古元古代末-新元古代重要地质事件.定年结果显示,北京西山寒武系徐庄组的钙质细砂岩中碎屑锆石年龄峰值主要集中在～1.38Ga和～1.14Ga.此外,还有～ 1.56Ga、～912Ma、～814Ma、～740Ma、～630Ma和～507Ma的年龄组.侏罗系窑坡组长石质岩屑细砂岩和粉砂质泥岩中碎屑锆石年龄峰值主要集中在～2.5Ga、1.88～1.8Ga、～1.74Ga、～1.6Ga和186Ma.此外,还有～2.77Ga、～2.0Ga、～1.2Ga、～488Ma、～256Ma和～233 Ma的年龄组.这三个岩石具有较低的成分和结构成熟度,指示较近的物源区,其碎屑物质可能大部分来自华北克拉通内部和北缘,因此其碎屑锆石的年龄组可记录华北克拉通前寒武纪重要地质事件.～2.77Ga、～2.5Ga、2.1～ 2.0Ga和1.88～1.8Ga的年龄组分别对应华北克拉通早前寒武纪发生地壳生长、克拉通化、裂谷和造山等重要地质事件；～ 1.74Ga、～ 1.6Ga、～ 1.56Ga、～1.38Ga、～912Ma和～814Ma的年龄组记录了华北克拉通最终克拉通化后开始的古元古代末-新元古代的多期裂谷事件.与1.3～ 1.0Ga、～740Ma和～630Ma的年龄组相对应的岩石在华北克拉通出现甚少,而该时期的岩浆岩和变质岩在华南克拉通广泛发育,且可能与Rodinia超大陆汇聚和裂解的不同阶段相对应.华北克拉通显生宙碎屑岩中碎屑锆石保存的古元古代末-新元古代地质事件的记录对探讨华北克拉通在元古宙的地质演化及华北克拉通与华南克拉通的关系可提供重要的依据.
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