海底电缆采集地震数据多次波压制处理

Multiple suppression of the seismic data collected by ocean-bottom cable

波动方程数值模拟与分析表明,浅海多次波与有效反射波耦合在一起,海平面强反射多次波改变了有效波波形与相位,降低了地震资料频率.针对海底电缆双检采集地震数据,在地震上行波波场与下行波波场分析和实际地震资料处理试验基础上,提出在对水检记录地震数据和陆检记录地震数据能量均衡后,进行地震数据合并压制多次波的便捷方法.并利用该方法对某浅海海域地震资料进行处理,叠前炮集对比和叠后偏移剖面对比分析都表明多次波得到有效压制,地震资料品质有较大程度提高,证明了方法的有效性.

The simulation and analysis of wave equation shows that the multiple waves couple with and the effective reflection wave under the condition of shallow water,the multiple waves reflected back from sea surface change the waveform and phase of the effective reflection wave and decrease the frequency of seismic data.Based on the analyses of up-going and down-going wave fields and the processing experience of the actual seismic data,a simple processing flow is presented for dual-sensor ocean-bottom cable traces.In the flow,the multiple waves are suppressed by the combination of the seismic data from pressure detector and onshore detector after the energy of the two types of seismic data is equalized.The comparison of pre-stack shot gathers and post-stack offset sections shows that the multiples reflected back from sea surface are effectively attenuated,and the quality of the seismic data is improved in great degree,which proves the effectiveness of the processing flow.