New explanation for shallow delta high-resolution sequence stratigraphy of Putaohua oil-bearing layer of member 1 of Yaojia formation of Cretaceous in Sanzhao sag

According to the data of seismic,well logging and cores,the research of shallow delta sequence stratigraphy of Putaohua oil-bearing layer of member 1 of Yaojia formation of Cretaceous in Sanzhao sag was carried out,and a high-resolution sequence stratigraphic framework was established.The results show that Putaohua oil-bearing layer amounts to the rising hemicycle of the long-term base-level cycle,and folding one middle-term base-level cycle which could be classified into eight short-term ones under the guidance of high-resolution sequence stratigraphy theory.The formation thickness is becoming small from north to south,because every sublayer is up-piching out bed by bed.Different correlation principles should be followed with interface(erosion surface),rock,interface(sedimentary discontinuity) along the source direction,and rock,interface cross the source direction.