Abstract:

In order to reveal and display the distribution law of the Paleogene stratigraphic-lithological reservoir of Qikou sag and provide guidance toward the drilling, this paper has utilized the sequence stratigraphy theory with the integration of 3D seismic data, well log data as well as core data to set the work of sequence stratigraphy analysis of it into motion. Paleogene, as a super sequence series, has developed three super sequences and 11 three-order sequences. According to the pattern of sedimentary structure slope break, the sequence can be divided into deflection break sequence and fault ramp sequence. The fault ramp sequence primarily develops in the super sequence 1, and the deflection break sequence mainly develops in the super sequence 2 and super sequence 3. In the Binhai slope area, the lowstand system tract sandstone of super sequence 2 and highstand system tract sandstone of super sequence 3, which are controlled by the deflection break and in well correlation to the high-quality source rocks of lake expansion system tract. The burial depth is fairly appropriate and reservoir formation conditions are superior, the area of which are favorable zones where stratigraphic-lithological reservoir highly develops. Furthermore, this paper has proposed the seismic attribute optimizing method involving the integration of forward modeling and the reservoir prediction under the control of seismic attribute. The application of these methods has successfully predicted six favorable targets in the target area, and the feasibility of which has been proved by the drilling results.

Key words: sequence stratigraphy, reservoir prediction, lithological-stratigraphic reservoir, Paleogene, Qikou depression, petroleum gas