杭锦旗地区上古生界层序及沉积体系发育特征

The characteristic of sequence stratigraphy and sedimentary systems of Taiyuan-Xiashihezi formation in Hangjinqi area

目的建立杭锦旗地区太原组—下石盒子组层序地层格架,明确沉积体系的发育特征。方法以岩心和测井资料为基础,通过层序界面的识别进行层序划分。结果杭锦旗地区晚古生代可划分为早、中及晚3个沉积演化阶段,分别对应LSC1-LSC3,LSC4-LSC5,LSC6长期旋回,主要发育障壁海岸沉积体系、扇三角洲沉积体系、冲积扇沉积体系和河流沉积体系。结论层序控制着沉积体系类型及特征,气藏主要分布在LSC4-LSC5的低位体系域的上部和水进体系域的下部。

Aim To set up the group sequence stratigraphic framework and to clearify the development characteristics of depositional systems of Taiyuan-Xiashihezi reservoir group in Hangjinqi area.Methods Based on the core and well logs,the sequences are classified by discriminated sequence boundaries.Results The sedimentary evolution of Late Paleozoic can be divided into three phases,respectively corresponding to the long term cycles of LSC1-LSC3,LSC4-LSC5 and LSC6.In the Upper Paleozoic four sedimentary systems of Barrier coast,Fan delta,Alluvial fan and Fluvial have been formed.Conclusion Sequences Controlled the types and characteristics of sedimentary systems.The gas reservoir is mainly distributed in the upper part of the lowerstand system tract and the lower part of the transgressive system tract of LSC4 and LSC5.