地震沉积学在苏里格49区块176三维区薄储层中的应用

Seismic sedimentary analysis of lower submember of He 8 member in Su 49 block

苏49区块位于苏里格西区西部,以薄互层储集层为主,现有三维地震资料主频较低,无法满足沉积相精细刻画需求。通过地震沉积学分析表明,研究区盒8下亚段发育由北向南的辫状河沉积体系,东西两侧各发育一条主河道,中间发育2-4条分支河道。沉积早期水动力能量波动大、沉积物供给不稳定,砂体单层厚度薄、泥质夹层多;晚期水动力能量强,沉积物供给丰富,砂体厚度大、岩性纯、物性好,形成相对优质的储集层。

Su 49 block is located in the western part of Sulige gas field,mainly in thin interlayer reservoirs,and the main frequency of the existing three-dimensional seismic data is too low to meet the needs of fine depiction of sedimentary facies.According to the analysis of seismic sedimentology,The results show that the lower submember of He 8 member in the study area develops a braided river sedimentary system from north to south,with two main river channels developing on the east and west sides,2~4 branch rivers developing in the middle.In the early stage of sedimentation,the hydrodynamic energy fluctuated greatly,the sediment supply was unstable,the single layer of sand was thin,and there were many slurry sandwiches;In the late stage,the hydrodynamic energy is strong,the sediment supply is abundant,the sand body thickness is large,the lithology is pure,and the physical properties are good,forming a relatively high-quality reservoir.