Tight oil sweet spot prediction with zero stripping: an example of Ek22 in Well G108 Block, Cangdong Sag
(2.Changqing Oilfield Company, PetroChina, Xi’an, Shaanxi, China 710200)
【Abstract】Different seismic phase characteristics extracted from complex deep interbeds usually show diversity on seismic slices. This problem makes tight oil sweet 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 were extracted from zero-value time, so interbed sandstones could be stripped step by step, and tight oil sweet spot prediction could be realized. The proposed approch was applied to Ek22 in Well G108 Block, Cangdong Sag. Tight oil sweet spots in upper sandstone of complex deep interbeds were successfully predicted from seismic data. The prediction coincided with the information of known wells, and good discoveries were found from the newly drilled wells proposed on our prediction.
【Keywords】 zero-value time; stripping method; Cangdong Sag; tight oil sweet spot; seismic slice;
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