Fluvial Reservoir Geological Modeling Controlled By Micro-facies

The reservoir sand of Fu Yang oil layer is arid environment fluvial deposition in the South of Song-Liao Basin. Comparing with the other areas, the sandstone/stratum is lower, the lateral variation of reservoir physical properties is larger, and the thickness of sand is thinner. Although, applying seismic techniques in reservoir study increase the accurate of lithologic prediction in recent years, the research can not precise identify the characters of reservoir distribution and the relationship between reservoir and hydrocarbon accumulation. As a result, the successful ratio of exploration well deployment to subtle oil-gas reservoir is lower than our expectation. Therefore, using geographic information processing and interpretation efficiently and reasonably, then fix the reservoir prediction by facies-controlled reservoir modeling is the key point to solve reservoir study problems at present.In this paper, we establish facies-controlled reservoir modeling suitable for fluvial reservoir of depression lake basin by utilizing seismic processing and interpretation information-with Fu Yang oil layer of the Zhao Yuan Nan as an example, which is based on mode determination reservoir prediction, conformation identification in high dip angle strata, fluvial sand body identification and facies-controlled reservoir model. Through the analysis for single well sequence stratigraphy and sedimentary facies features, obtain the type of sedimentary facies in each stratum. We developed seismic relative amplitude preserved processing flow experiment, formed a seismic relative amplitude preserved processing flow suitable for sedimentary characteristics of Fu Yang oil layer. Target layer sequence stratigraphic framework of Zhao Yuan Nan is determined, then, seismic horizon correspondence with third-order sequence can be interpreted. We get reservoir thickness of each fourth order sequences; implement fine reservoir prediction of thin-interbedded sandstone. The distribution characters of meandering river point bar has been depicted based on many techniques of seismic sedimentology basic principle, seismic relative amplitude preserved processing results, seismic horizon flattening interpretation using the reference layer and reservoir identification by short time window seismic attribute. The subtle micro-range structure can be recognized by means of fine structural map and weakening structural trend. Plane sedimentary facie zones of each stratum were divided, and then build geological model base on the result of fine reservoir prediction of thin-nterbedded sandstone and fluvial sand body identification. Finally, we build fine geological model of Zhao Yuan Nan, and propose drilling targets by researching the spatially distributing feature of reservoir and reservoir forming stress conditions through the application of fine geological model. It effectively solved the problem that effective reservoir was hard to prediction and does not math the reservoir-forming dynamic. Through the studies that mentioned above, the following essential awareness and conclusions had been made in this dissertation:1. This research work predicts geologic structural association of average seismic trace by the means of mode determination reservoir prediction technology in areas less well data. reservoir thickness of each fourth order sequences was be predicted, fine reservoir prediction in single sand body level was realized without influence of strong high energy shield.2. The subtle micro-range structure can be recognized by fine structural map and weakening structural trend in high dip angle strata. By using this method, one hand we can highlight subtle micro-range structure, on the other hand, we can keep region structural shape. So we can find out an easy way to identify the subtle micro-range structure.3. We divvied dominant sedimentary facies by the combination of mode determination reservoir prediction and the result of single well sedimentary facies.This method is suitable for geological setting model from final exploration period to earlier reservoir evaluation. It has been applied in Chao Chang district of the South of Song-Liao Basin, and achieved successful result in recent years.