改进的RTM成像在涠西工区的应用

Application of Improved RTM Imaging in Weixi Block

张大海 赵秀莲 徐颖

ZHANG Dahai ZHAO Xiulian XU Ying

中国石油化工股份有限公司上海海洋油气分公司勘探开发研究院，上海　200120 中国石油化工股份有限公司南京物探技术研究院，江苏南京　210000

Institute of Exploration and Development, SINOPEC Shanghai Offshore Oil & Gas Company, Shanghai 200120, China Institute of SINOPEC Nanjing Geophysical Prospecting Technology, Nanjing Jiangsu 210000, China

为了提高涠西工区大断裂及小断层成像效果，通过在涠西工区应用叠前逆时偏移技术（RTM）多轮次的测试分析及试处理，找到了影响海上复杂构造的RTM成像效果的关键问题，针对性开展了单边放炮观测孔径定义方式、宽屏RTM算法（低频保护的Laplace算法优化）和RTM照明补偿等技术方法优化，并开发了相应的RTM模块。测试应用结果形成了一套RTM技术在涠西区块精细成像的技术参数。RTM成像处理效果在研究过程中逐步大幅提高，大断层成像、断点的归位比以往成果及此次叠前深度偏移更加清晰、准确，构造成像可信度提高，基底构造连续清晰，尤其在陡倾角地层及小断层成像效果较好。

In order to improve the imaging effect of large faults and small faults in Weixi block, through the application of pre-stack reverse time migration technology for the test analysis and trial treatment of multiple rounds, the key problem which affects the RTM imaging effect of offshore complex structures has been found. Technical methods have been optimized such as unilateral gun observation aperture definition, widescreen RTM algorithm (optimization of Laplace algorithm for low frequency protection) and RTM illumination compensation. Corresponding RTM modules also have been developed. The results of the test application have formed a set of technical parameters about RTM technology for fine imaging in Weixi block. The effect of RTM imaging processing has been gradually improved in the research process. The large tomography and the fault point relocation are clearer and more accurate than the previous results and the depth before the stacking, the credibility of structural imaging is improved, the basement structure is continuously clear, especially in the effect of steep inclination formation and small tomography becomes better.

https://doi.org/10.3969/j.issn.1008-2336.2021.04.001