地震沉积学在渤海A油田中的应用

Application of Seismic Sedimentology to A Oilfield of Bohai Sea

别旭伟 廖新武 许赛男

BIE Xuwei LIAO Xinwu XU Sainan

中海石油(中国)有限公司天津分公司, 天津塘沽 300452

Tianjin Branch of CNOOC Ltd., Tanggu Tianjin, 300452, China

地震沉积学在高频率层序和沉积体系的研究中有着特殊的优势。90°相位地震资料的振幅可以和岩性测井曲线对应,对地震资料进行90°相位调整后可以通过地震振幅分析岩相。地层切片技术可以在平面上显示相对同一地质沉积时间的沉积分布特征,再结合岩性测井资料可以较准确分析沉积体系。针对渤海A油田开发井钻前面临的被动局面,在研究区开展地震沉积学研究,在相位调整的基础上,通过对一系列地层切片的研究,结合钻井岩心信息进行动态解释,获得了研究层段从下至上主要经历了枝状的分流河道型三角洲以及连片的分流砂坝型三角洲的沉积演化过程的认识。同时在成藏规律指导下,预测出该油田5个有利岩性砂体,钻后均得到证实,获得探明石油地质储量超1 200×104m3,扭转了A油田开发被动的局面,为该区其他油田的勘探和开发提供了经验。

Seismic sedimentologic analysis is superior to conventional seismic stratigraphic analysis in high-frequency and deposi-tional system study. 90°-phase seismic amplitudes can be correlated to log lithologies, and consequently, after phase shift on seismic data, seismic amplitudes can be used for lithologic analysis. The strata slice technology made form the 3-D seismic volume can be used to reveal the distribution characteristics of deposits deposited at the same geologic time, and combined with lithologic log data, the depositional systems can be analyzed accurately on the relative same geologic time surfaces. For the A oilfield, before drilling the development wells, a seismic sedimentology study has been conducted for the target zones. On the basis of the 90°-phased shift, a dynamic interpretation has been done to the target zone through study on a series of stratal slices combined with the drilling core information. It is concluded through interpretation that distributary channel to the distributary bar deposits are dominated in the target zones. Base on the HC accumulation rules, five favorable sand bodies have been forecasted and confirmed through well drilling, and over 1 200×104 m3 proved OOIP has been obtained, changing the unfavorable development conditions of A oilfield of Bohai Sea. In addition, the experience in A oilfield can provide reference for the exploration & development in the other oil fields of this area.

https://doi.org/10.3969/j.issn.1008-2336.2013.01.044