Fracture prediction method for narrow-azimuth seismic data of offshore streamer acquisition
Liu Dao-Li, Yang Xue-Qi, Zou Ya-Ming, Liu Xu-Min, Wang Guo-Quan, and Chen Shuang-Quan
1. CNOOC Deep Sea Development Co., LTD, Shen Zhen 518054, China;
2. CNPC Key Laboratory of Geophysical Exploration, China University of Petroleum (Beijing) 102249, China
Abstract：
Considering the constraints in the costs and efficiency of seismic exploration acquisition, marine hydrocarbon exploration mainly relies on towed-streamer acquisition. However, the seismic data obtained from streamers have limited azimuthal coverage, posing significant challenges for the prediction of complex fractured reservoirs using azimuthal anisotropy features. To address this issue, we proposed a workflow for conventional offshore narrow-azimuth streamer data, including the local angle domain migration imaging and prestack anisotropy inversion methods based on the Rüger approximation equation. First, the local angle domain full-azimuth migration imaging method is used to perform prestack imaging processing on narrow-azimuth streamer seismic data, thus obtaining prestack gather data with azimuth information. The prestack anisotropy parameter inversion method is then used to predict the fracture intensity distribution. Finally, the method and technical process proposed in this paper are applied to the fractured reservoir description of buried hills reservoirs in the deepwater area of the northern South China Sea. The practical results demonstrate that the proposed workflow, which combines full-azimuth migration imaging processing and prestack azimuthal anisotropy parameter inversion, can accurately predict fractured reservoirs using narrow-azimuth seismic data acquired through marine towed-streamer surveys. This technical workflow is also applicable to fracture predictions and reservoir evaluations in similar seismic survey areas.
2024, Vol. 21 
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