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河北涞源祁家峪剖面寒武系出露连续,层序界面清楚且沉积现象丰富,是进行华北地台寒武系层序划分的较为典型的剖面之一。在新的寒武系年代地层框架下,依据地层的叠置形式、纵向上的沉积相变化及其内部的旋回特征,将该剖面寒武系划分为8个三级层序。结果表明:研究区域从馒头组、毛庄组的“TST+HST”沉积序列转变为“CS+HST”的淹没不整合型层序序列,反映出从混积潮坪沉积序列向缓坡型碳酸盐台地的演化过程,也意味着华北地台寒武系碳酸盐台地从发展阶段向成熟阶段的重大转变;该剖面芙蓉统内部的竹叶状灰岩与长山组顶部、凤山组第1个三级层序顶部发育的均一石生物丘代表了华北地台寒武系末期“贫乏骨骼的风暴海”以及“随着后生动物辐射,微生物碳酸盐岩也在增加”两大特殊沉积现象较为典型的沉积样式。基于层序地层框架内的沉积相叠加方式和地层记录中旋回特征的描述,对河北涞源祁家峪剖面进行层序地层划分,将为探索华北地台在太行山北缘广泛分布的寒武系提供参考实例,也为今后更大区域范围的对比研究提供线索。
The Cambrian of Qiyuanyu section in Laiyuan County, Hebei Province is exposed continuously with a clear sequence boundary and abundant sedimentary facies. It is one of the typical sections for the Cambrian sequence division in North China. Under the framework of the new Cambrian chronostratigraphy, the Cambrian of this section is divided into 8 third-order sequences according to the superimposition of strata, vertical sedimentary facies changes and their internal gyration characteristics. The results showed that the study area was changed from the “TST + HST” sedimentary sequence of “Mianzhuang Formation” and “Maozhuang Formation” to the “inundated unconformity sequence” of “CS + HST”, reflecting that from the tidal flat sedimentary sequence The evolution of the gentle slope carbonate platform also implies that the Cambrian carbonate platform in North China changed greatly from the developmental stage to the mature stage. In the section, The homogeneous stone bio-mound developed at the top of the first third-order sequence of the Fengshan Formation represents the end of the Cambrian to the “storms of poor skeletons” in the North China Platform. As the metazoan radiation, microbial carbonate rocks In the increase "two special deposition phenomenon is more typical of the deposition pattern. Based on the superimposition of sedimentary facies in the sequence stratigraphic framework and the description of the gyration characteristics in the stratigraphic record, the stratigraphic sequence stratigraphic division of Qijiyu section in Laiyuan, Hebei Province will be conducted to explore the Cambrian Provide reference examples, and provide clues for the comparative study of the larger regional scope in the future.