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.