Identification of gas reservoir related with bright spots and thin-bed tuning
Liu Wei1,2, Cao Siyuan1,2
1. State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum (Beijing), Beijing 102249, China;
2. CNPC Key Laboratory of Geophysical Exploration, China University of Petroleum (Beijing), Beijing 102249, China
Abstract：To distinguish true and false bright spots is a key for stratigraphical reservoir exploration. False bright spots caused by thin-bed tuning effect are often present in post-stack seismic data. This kind of false bright spots is totally different from true bright spots associated with gas reservoir. Based on petrophysical parameters of real reservoirs, we design geological models of wedge and thin-beds, and simulate thin-bed tuning effect. Therefore we analyze both the relationship between thin-bed tuning and frequency, and the relationship between gas reservoir and frequency. Tests results on Marmous Ⅱ model indicates that high amplitude caused by thin-bed tuning can be distinguished from that caused by gas reservoir based on normalized different mono-frequency sections obtained with time-frequency continuous wavelet transform. This provides a new approach to distinguish true or false bright spots on post-stack seismic data. Field examples illustrate that the proposed method identifies effectively gas reservoirs so that the risk of stratigraphical reservoir exploration is reduced.
刘伟, 曹思远. “亮点”型含气储层与薄层调谐的识别[J]. 石油地球物理勘探, 2015, 50(4): 678-683,705.
Liu Wei, Cao Siyuan. Identification of gas reservoir related with bright spots and thin-bed tuning. OGP, 2015, 50(4): 678-683,705.
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