Research Of The Changxing Organic Reef Distributed And Seismic Recognition Techniques, East Sichuan Basin

D block Carboniferous gas reservoir is mainly constructed by the lithologic-trapped gas reservoir。Changxing group reef reservoir is characterized by porosity. The type of the main reservoir is Pore-fractured type. Changxing group gas reservoir is controlled by lithology. The organic reefs characters are wide distributed, small in size, and the difference between reef and wall rock is great. It also has a strong heterogeneity, uneven vertical and horizontal distribution and a deep burial, etc. It brings out a great difficulty for the recognition of the structure, reservoir and the fluid character in this aera.According to the special geological structure and the reservoir character, seismic and logging information is collected to determine its reliability. Based on the accurate horizon definition, the bottom of the Feixianguan group, the implementation of its structural form, the distribution of fault conditions and the trap of mutual contacts between the relations are precisely interpreted. The organic reef formation and distributed scale are controlled by the " Kaijiang Iiangping "trough palaeogeomorphology formed at the end of "Longtan" period and sustained sea transgression during the Changxing period in the eastern part of Sichuan Basin. The platform margin facies on both sides of the "Kaijiang-Iiangping" trough are the favorable regions of organic reef growth.In order to have a further study of this aera, we'd better study the unique characteristics of the environment. We defied the sedimentary facies by the drilling data. With the help of the well data in this area its adjacent area, we get the forward model. Under the guidance of the model, we defied the seismic facies by amplitude envelope, RMS amplitude and instantaneous phase of technology, etc. Combined with spectral imaging technology and the theory of absorption and attenuation, we successfully get the further refinement of the reef edge. Based on the select band of the reef reservoir inversion analysis and the forecasted reef edge of the reservoir distribution, we identify the spatial distribution potential areas of the D block Reef gas reservoir. In all, this research enriched and developed the carbonate reservoir prediction technique with seismic data and has opened up broad prospects for Changxing organic reef carbonate reservoir prediction.