Research on seismic reservoir prediction technology for deeply buried marine carbonate rock buried hill in Bozhong Sag

Author of the article:WANG Siquan, DIAO Juncai, QIN Dehai, SUN Zhe

Author's Workplace：Bohai Oilfield Research Institute, CNOOC China Ltd., Tianjin Branch, Tianjin, 300459, China

Key Words：Carbonate rock buried hill; Smooth reflection intensity filtering; Reservoir sensitive factor; Pre-stack elastic parameter inversion

Abstract：The marine carbonate rock buried hill fracture and dissolution pore system in Bozhong Sag is well-developed, resulting in strong reservoir heterogeneity. Due to the low signal-to-noise ratio of seismic data and the unclear seismic response characteristics of high-quality reservoirs in the B structure of Bozhong Sag, it is challenging to predict the seismic response of carbonate rock buried hill reservoirs. To address this issue, based on conventional fracture detection, this paper introduces a denoising technology based on smooth reflection intensity filtering and optimizes the ant body attributes sensitive to buried hill fractures to carry out fracture prediction, forming a high-precision post-stack fracture detection technology. At the same time, a new pre-stack inversion technology for carbonate reservoir sensitive factors with anti-lithologic interference is established by integrating P-wave velocities sensitive to fractures and pores with density parameters sensitive to lithology. High-precision post-stack fracture detection under low signal-to-noise ratio is realized, and the recognition accuracy of pre-stack elastic parameters for high-quality reservoirs under complex lithology conditions is improved. The successful application in the Bohai B structure shows that the developed seismic prediction technology for marine carbonate rock buried hill reservoirs can achieve direct prediction of high-quality carbonate rock reservoirs. The research findings can provide reference for seismic reservoir prediction in carbonate rock buried hill of the same nature.