零值剥离法在致密油甜点体预测中的应用——以沧东凹陷G108井区Ek2^2为例

Tight oil sweet spot prediction with zero stripping:an example of Ek_2~2 in Well G108 Block,Cangdong Sag

针对深层复杂岩性互层组合形成的地震反射在其不同相位提取的地震切片呈现出多样性特征的难点问题,通过建立三维地震地质模型并对三维正演数据体进行分析,提出了零值剥离法砂体预测技术,即在零值点处提取的地震切片可以实现互层砂体信息的逐层剥离,从而较准确地预测出有效砂体。在沧东凹陷Ek 22上部砂体预测应用中,实现了在深层复杂岩性互层组合对应的地震反射中预测出致密油甜点体,预测结果与已知井特征吻合,并成功指导了新井部署。

Different seismic phase characteristics extracted from complex deep interbeds usually show diversity on seismic slices.This problem makes tight oil sweat spot prediction very difficult.Therefore we put forward in this paper a zero stripping prediction approach through three-dimensional seismic-geological model building and three-dimensional forward modeling data analysis.Seismic slices are extracted from zero-value time,so interbed sandstones can be stripped step by step,and tight oil sweet spot prediction can be realized.The proposed approch is applied to Ek_2~2 in Well G108 Block,Cangdong Sag.Tight oil sweet spots in upper sandstone of complex deep interbeds are successfully predicted from seismic data.The prediction coincides with the information of known wells,and good discoveries are found from the newly drilled wells proposed on our prediction.