高分辨率地震采集系统中的频谱均衡滤波器设计

Design of spectral balancing filter in high-resolution seismic acquisition system

本文用地震纵波速度表示地层吸收衰减特性,建立视等厚层状吸收介质模型,给出频谱均衡滤波器的数学模型和设计框图。选择主频为200Hz的雷克子波,对理想、实际和均衡滤波后的地震反射数据进行计算机正演模拟分析。结果表明,所设计的频谱均衡滤波器能够对弱的高频信号进行有效补偿,使分辨率的提高效果明显。由浅层到深层(时间从O.5～3.0s),实际地震反射的垂向分辨厚度为7.4～45.7m,均衡滤波以后垂向分辨厚度为3.6～17.4m,相对地层吸收衰减分辨率提高百分比为82.6%～75.9%,这对高分辨率地震数据采集和研发新一代地震仪具有指导意义。

Using seismic P-wave velocity to show the feature of attenuation by absorption of stratum, the paper creates apparent isopachous layered absorption medium model and gives math model and designing flow chart of spectral balancing filter. Selecting Rick wavelet with 200 Hz dominant frequency,the forward simulation and analysis by computer are carried out for ideal,practical and post-balancing filtering seismic reflection data. The results showed that the designed spectral balancing filter can implement effective compensation to weak high-frequency signals,making the resolution he greatly improved.The vertical identified thickness from practical seismic reflections is 7.4～45.7m from shallow to deep horizons(time is 0.5～3.0s),and vertical identified thickness after balancing filtering is 3.6～17.4m,and the relative resolution of attenuation by absorption of stratum has been raised to 82.6～75.9%,which has guide meaning for high-resolution seismic data acquisition and development new-generation seismograph.