海洋宽频地震数据瞬时相位梯度属性计算方法及优势分析  

Calculation method and advantage analysis of instantaneous phase gradient attributes for offshore broadband seismic data

作　　者：叶云飞 焦振华 陶杰 YE Yunfei;JIAO Zhenhua;TAO Jie(CNOOC Research Institute Ltd.,Beijing100028,China)

机构地区：[1]中海油研究总院有限责任公司,北京100028

出　　处：《中国海上油气》2021年第4期46-53,共8页China Offshore Oil and Gas

基　　金：“十三五”国家科技重大专项“南海深水区油气勘探地球物理关键技术(编号:2016ZX05026-001)”部分研究成果。

摘　　要：与常规地震数据相比,海洋宽频地震数据中子波的波形、相位和频率特征均发生了显著变化,在改善中深层地震成像精度、提高储层预测和油气检测准确性方面具有许多明显优势。对地震资料进行Hilbert变换后的“三瞬”属性提取技术在地震层序解释、勘探研究中得到了广泛应用,但并没有考虑瞬时相位的不连续性与层序界面之间的关系,而且在显示沉积层序界面位置时也往往不够直观。本文针对宽频地震数据提出了一种保留子波相位卷绕特征的瞬时相位梯度属性计算方法,通过模拟试验分析了常规子波和宽频子波的相位卷绕现象及在瞬时相位梯度计算中的差异,并通过正演模型剖析了宽频地震数据瞬时相位梯度属性优势及产生原因。南海深水区应用表明,利用本文方法所计算的瞬时相位梯度属性剖面可以很好地展示出水道分布形态,进而清晰地刻画出水道中沉积层序及其变化规律。Compared with conventional seismic data,the waveform,phase and frequency characteristics of neutron wave in marine broadband seismic data change significantly,they have many obvious advantages in improving the accuracies of seismic imaging and reservoir prediction as well as oil and gas detection in medium and deep strata.The three-instantaneous(instantaneous amplitude,frequency and phase)attribute extraction technology obtained from Hilbert transform of seismic data has been widely used in seismic sequence interpretation and exploration research,but it does not consider the relationship between the discontinuity of instantaneous phase and the sequence interface,and either it is not intuitive to display the location of sedimentary sequence interface.As to offshore broadband seismic data,we proposed a method of calculating instantaneous phase gradient attribute which retains the convolution characteristics of wavelet phase,analyzed the conventional wavelet and broadband wavelet phase convolution phenomenon and the differences among results of instantaneous phase gradient calculation through simulation,and we further analyzed the advantage and the reason of the instantaneous phase gradient attribute for broadband seismic data through forward modeling.The application in the deep water of South China Sea shows that the instantaneous phase gradient attribute profile shows a clear distribution of water channels,and unfolds the sedimentary sequence and its change law in the water channels.

关 键 词：宽频地震 相位卷绕 瞬时相位梯度 优势分析 深水区 

分 类 号：TE132.14[石油与天然气工程—油气勘探]