山前带地震资料噪声消除中存在的问题与对策

摘要

针对山前带低信噪比地震资料的去噪问题,以随机噪声和相干噪声为例,对目前应用的去噪技术及其效果进行了系统的分析.首先根据常用的随机噪声消除技术应用条件,指出现行随机噪声消除技术不能准确消除低信噪比资料中的随机噪声,提出在叠加/偏移后进行随机噪声消除的对策,并运用理论模型验证了这一方法.其次根据山前带相干噪声能量强、范围广的特点,针对现有相干噪声消除技术均不能完全消除相干噪声的问题,提出压制残余相干噪声的客观度量方法:残余相干噪声能量小于有效信号能量.最后通过KD地区实际资料处理证实了这种做法的合理性.%Aiming at the de-nosing of the seismic data with low S/N in foothill area,taking random noise and coherent noise as examples, we systematically analyzed the conventional de-noising techniques and their effect. Firstly, in terms of the application conditions of conventional de-noising technique for random noise,it was pointed out that the existing techniques cannot accurately remove the random noise of the seismic data with low S/N; meanwhile, we proposed to remove random noise after stack/migration and proved the method by theoretical model. Secondly, in terms of the strong energy and wide distribution of coherent noise in foothill area, we put forward the objective measurement method that residual energy of coherent noise is weaker than the signal energy. The application in KD area proved the reasonability of the method.