南黄海地震资料叠前去噪技术应用

南黄海盆地位于下扬子地台东北部,是一个由多期、多类型盆地叠加的复合残留盆地,平均水深约为50 m。工区内地震资料信噪比较低,干扰波类型较多,主要有涌浪、电缆和水鸟等产生的随机噪声,线性噪声和船干扰等相干噪声。通过系统分析噪声在振幅、频率方面的特征,以及噪声产生的机制,分别在不同域采用多种压制方法,主要采用分频分时振幅衰减技术去除异常振幅噪声,f-x域相干噪音方法压制低速线性噪声干扰,外部噪音模型法压制高速线性噪声,τ-p域切除法去除直达波干 扰,以及采用fxy域预测误差方法压制船干扰噪声等。通过以上叠前多域去噪技术方法,在尽量不损害有效信号的情况下,对南黄海地震数据的各种噪声进行很好的压制。

APPLICATION OF PRE-STACK NOISE SUPPRESSION TECHNIQUE IN THE SOUTH YELLOW SEA

The South Yellow Sea Basin is located on the northeastern Yangtze platform,as a multi-phase and multi-class superimposed composite residual basin with an average water depth of about 50 meters.As to seismic survey in this area,the signal-to-noise ratio is low by the interference of many types of waves, such as the random noise,linear noise and ship generated coherent noise waves caused by swell,cable and waterfowl.By the systematic analysis of the characteristics of noises in amplitude and frequency,as well as the mechanism of noise generation,a variety of methods are used to suppress noises in different domains separately,for examples,the frequency division and time division amplitude attenuation technique is used to remove abnormal amplitude noise,the f-x domain coherent noise suppression method to remove linear low noise,the external noise model method to suppress high-speed linear noise,the τ-p domain excision method to suppress the direct wave interference,and the fxy domain prediction error method to suppress ship interference noise.Through the above mentioned pre-stack multi-domain noise suppression,the noises are effectively suppressed in the South Yellow Sea without damage of effective signals.