CAJ | 학술논문

针对逆时偏移低频背景噪声压制问题，开展了相对保幅性去噪方法研究。从热力学传导方程出发，构建了三维扩散滤波数值计算公式并进行了简化，详细探讨了所提方法低频噪声的压制机理。以实际三维地震资料叠前逆时偏移数据为例，对比了邻点加权平滑滤波法、扩散滤波法和高通滤波法三种低频噪声压制方法的去噪效果及其频谱，同时对去噪前和去噪后的水平切片振幅曲线和深度域波形曲线进行相对保幅性分析。结果表明：扩散滤波方法可通过调节迭代次数实现不同压制程度的低频去噪效果，具有最佳的相对保幅性，同时频带更宽，频谱能量更均匀，这对实际资料逆时偏移处理具有重要的借鉴意义。
침대역시편이저빈배경조성압제문제，개전료상대보폭성거조방법연구。종열역학전도방정출발，구건료삼유확산려파수치계산공식병진행료간화，상세탐토료소제방법저빈조성적압제궤리。이실제삼유지진자료첩전역시편이수거위례，대비료린점가권평활려파법、확산려파법화고통려파법삼충저빈조성압제방법적거조효과급기빈보，동시대거조전화거조후적수평절편진폭곡선화심도역파형곡선진행상대보폭성분석。결과표명：확산려파방법가통과조절질대차수실현불동압제정도적저빈거조효과，구유최가적상대보폭성，동시빈대경관，빈보능량경균균，저대실제자료역시편이처리구유중요적차감의의。
In order to suppress the low-frequency background noise of reverse-time migration, studies were carried out on noise suppression method of relatively amplitude preservation performance. Started from thermal conduction equation, 3D diffusion filter-ing numerical computational equation was constructed and simplified further for the detail discussion of the proposed method's low-frequency noise suppression mechanism. Taking practical 3D seismic pre-stack reverse-time migration data as an example, noise suppression results and their spectrum of three kinds of low- frequency noise suppression methods, that is adjacent weighted smoothing filtering method, diffusion filtering method and high-pass filtering method were compared. Meanwhile, relatively ampli-tude preservation was analyzed on horizontal slice amplitude curve and waveform curve in depth domain before and after noise sup-pression. The results show that the diffusion filtering method can achieve low-frequency noise suppression in different suppression degree by adjusting the iterative frequency and has the best relatively amplitude preservation performance with wider frequency band and more even spectrum energy. Therefore, it has important model significance to the practical seismic reverse-time migra-tion data processing.