北京西山淹没不整合型高频旋回层序地层研究

Study on Submerged Unconformity Type High Frequency Cyclic Sequence Stratigraphy in Xishan Mountain,Beijing

以北京西山寒武系张夏组地层为例,运用米兰柯维奇高频旋回层序地层分析方法与地球化学结合研究的手段,对三级快速海侵背景下的寒武系张夏组高频旋回层序地层格架进行划分。研究认为,该区张夏组灰岩地层并非传统的I、II型碳酸盐岩层序模式,应为典型淹没不整合型层序。建立了从三级层序到六级米级旋回的张夏组淹没不整合型高频旋回层序地层格架。淹没不整合型层序格架内有利储层主要发育于三级、四级层序的高水位体系域中。快速海侵事件标志着碳酸盐岩台地的沉积间断。通过对淹没不整合型碳酸盐岩层序地层的研究来指导未来的石油勘探生产,具有现实的研究意义。

Taking the Cambrian Zhangxia Formation in Xishan mountain,Beijing for example,by means of combining the Milankovitch high frequency cyclic sequence stratigraphy analytic method with the geochemical study,this paper conducted division to the Cambrian Zhangxia Formation high frequency cyclic sequence stratigraphy framework under a third order fast transgression setting. It was believed based on study that the Zhangxia Formation limestone formation in the area was not the traditional type I and II carbonate sequence pattern,and it should be a typical submerged unconformity type sequence. This paper built a Zhangxia Formation submerged unconformity type high frequency cyclic sequence stratigraphy framework from third order sequence to sixth order meter- level cycle. The favorable reservoir in the submerged unconformity type sequence framework was mainly developed in the highstand system tract of third order and fourth order sequences. The fast transgression event marked the depositional brek of carbonate platform.It has realistic study significance to use the study of submerged unconformity type carbonate sequence stratigraphy to guide the petroleum exploration and production in the future.