High-Resolution Inversion and Spectral Decomposition: Case Studies from the Bohaiwan Basin, China

The Jiyang and Liaohe sub-basins of the Bohaiwan basin in China are Cenozoic rift basins containing active production. In these areas, reservoir thickness below seismic resolution limits the utility of conventional seismic data for reservoir characterization. In the Jiyang area, lacustrine shoreline thin-sand bodies are interbedded with shales, which makes it difficult to detect or map the lateral continuity of these reservoirs. Volcanic activity in the Liaohe area resulted in basalt layers with strong reflectivity adjacent to sandstone reservoirs. This makes it difficult to image the reservoir as side lobes of the strong base basalt reflector obscure the reservoir. In addition, the sand reservoir is below the resolution limit of conventional seismic data, which causes great uncertainty and risk. To improve the detectability and resolution, sparse-layer inversion was applied to the conditioned 3D data. The inverted results successfully resolved the target sand layers and showed great improvement in seismic resolution. Understanding of the distribution of reservoir sand packages is also enhanced. RGB blending of spectrally decomposed seismic data helps to identify more details of the stacked channel pattern of the Neogene fluvial system in the Jiyang dataset, as it varies from a braided river system to a meandering river system morphology.Earth and Atmospheric Sciences, Department o