Meandering channel sandstone architecture characterization based on architecture seismic forward simulation

Abstract

To improve the accuracy of the meandering channel sandstone reservoir characterization in offshore oilfield, this article completes the meandering channel sandstone reservoir architecture characterization of the NmII-3 layer of Low Minghuazhen Group in the Qinhuangdao 32-6 oilfield by the architecture-guided seismic forward simulation based on the meandering river depositional mechanism. By the research mentioned above, the seismic forward simulation identification criteria of composited meandering channels boundaries are summarized that when the mud layer thickness is greater than or equal to 1 m and the channel sandstone thickness is between 8 and 9 m, the mud layer between composite meandering channels can be identified. The seismic forward simulation identification criteria of single meandering channels boundaries are summarized that the elevation difference which is greater than or equal to 5 m can be identified while the channel sandstone is greater than or equal to 7 m. And the seismic forward simulation waveform features of elevation difference of channels, small sandstone among channels, and abandoned channel are summarized. The seismic waveform of elevation difference has two side-by-side troughs. The seismic crest center position of large channel sandstone is lower than the seismic crest center position of the small sandstone. The seismic crest center falls slowly and rises quickly from convex bank to concave bank in abandoned channel laterally. Finally, the architecture-guided seismic forward simulation method is established and the applying criteria are summarized in this paper. And the accuracy of the meandering channel sandstone architecture characterization with well logs and seismic data is improved.