南黄海盆地中部隆起区前第三系油气储层主要为中古生代海相碳酸盐岩地层,厚度大、分布广,具有良好的油气前景.由于厚度小于1000 m的新近系低速地层直接覆盖在高速碳酸盐岩地层之上,对地震波的向下传播起到了强烈的屏蔽作用,使之深部目...南黄海盆地中部隆起区前第三系油气储层主要为中古生代海相碳酸盐岩地层,厚度大、分布广,具有良好的油气前景.由于厚度小于1000 m的新近系低速地层直接覆盖在高速碳酸盐岩地层之上,对地震波的向下传播起到了强烈的屏蔽作用,使之深部目的层地震资料品质差,影响了油气勘探的进程.根据区域地质、地球物理特征,进行了基于AVO(Amplitude Versus Offset,振幅随偏移距变化)与地震波吸收衰减的地震反射振幅理论模拟分析,获得了主要反射界面的地震反射振幅与偏移距关系.在对不同气枪、电缆沉放组合的震源子波特征模拟分析的基础上,重点选取波形好、穿透能力强的气枪、电缆沉放组合系列,通过试验选择了适宜的采集参数进行地震资料采集,获得了有效深部弱反射地震信号.展开更多
Seismic imaging of complicated underground structures with severe surface undulation(i.e.,double complex areas)is challenging owing to the difficulty of collecting the very weak reflected signal.Enhancing the weak sig...Seismic imaging of complicated underground structures with severe surface undulation(i.e.,double complex areas)is challenging owing to the difficulty of collecting the very weak reflected signal.Enhancing the weak signal is difficult even with state-of-the-art multi-domain and multidimensional prestack denoising techniques.This paper presents a time–space dip analysis of offset vector tile(OVT)domain data based on theτ-p transform.The proposed N-th root slant stack method enhances the signal in a three-dimensionalτ-p domain by establishing a zero-offset time-dip seismic attribute trace and calculating the coherence values of a given data sub-volume(i.e.,inline,crossline,time),which are then used to recalculate the data.After sorting,the new data provide a solid foundation for obtaining the optimal N value of the N-th root slant stack,which is used to enhance a weak signal.The proposed method was applied to denoising low signal-to-noise ratio(SNR)data from Western China.The optimal N value was determined for improving the SNR in deep strata,and the weak seismic signal was enhanced.The results showed that the proposed method effectively suppressed noise in low-SNR data.展开更多
文摘南黄海盆地中部隆起区前第三系油气储层主要为中古生代海相碳酸盐岩地层,厚度大、分布广,具有良好的油气前景.由于厚度小于1000 m的新近系低速地层直接覆盖在高速碳酸盐岩地层之上,对地震波的向下传播起到了强烈的屏蔽作用,使之深部目的层地震资料品质差,影响了油气勘探的进程.根据区域地质、地球物理特征,进行了基于AVO(Amplitude Versus Offset,振幅随偏移距变化)与地震波吸收衰减的地震反射振幅理论模拟分析,获得了主要反射界面的地震反射振幅与偏移距关系.在对不同气枪、电缆沉放组合的震源子波特征模拟分析的基础上,重点选取波形好、穿透能力强的气枪、电缆沉放组合系列,通过试验选择了适宜的采集参数进行地震资料采集,获得了有效深部弱反射地震信号.
文摘Seismic imaging of complicated underground structures with severe surface undulation(i.e.,double complex areas)is challenging owing to the difficulty of collecting the very weak reflected signal.Enhancing the weak signal is difficult even with state-of-the-art multi-domain and multidimensional prestack denoising techniques.This paper presents a time–space dip analysis of offset vector tile(OVT)domain data based on theτ-p transform.The proposed N-th root slant stack method enhances the signal in a three-dimensionalτ-p domain by establishing a zero-offset time-dip seismic attribute trace and calculating the coherence values of a given data sub-volume(i.e.,inline,crossline,time),which are then used to recalculate the data.After sorting,the new data provide a solid foundation for obtaining the optimal N value of the N-th root slant stack,which is used to enhance a weak signal.The proposed method was applied to denoising low signal-to-noise ratio(SNR)data from Western China.The optimal N value was determined for improving the SNR in deep strata,and the weak seismic signal was enhanced.The results showed that the proposed method effectively suppressed noise in low-SNR data.
