频率—波数域水陆检数据上、下行波场分离方法

Method of up⁃going and down⁃going wavefield separation in the frequency⁃wavenumber domain for dual⁃sensor seismic data

随着海洋油气勘探开发的发展,OBC/OBN水陆检海底接收的应用日趋广泛,上、下行波场分离作为水陆检数据处理的关键技术,决定了资料处理品质及应用效果。常规方法分离出来的上行波场中包含下行波场,下行波场中包含上行波场,即不能实现上行波场与下行波场的完全分离。为此,提出在频率—波数域利用包含直达波和切除直达波后的水陆检数据,直接计算水陆检数据标定滤波因子,实现水陆检数据标定和上、下行波场分离。分离后的上行波场数据中既消除了虚反射多次波干扰,又提高了地震数据信噪比和分辨率,为后续联合反褶积和偏移成像等处理提供了高保真的上行波场和下行波场数据。数据实例表明了所提方法的有效性和实用性。

With the advancement of offshore oil and gas exploration and development,the application of dual-sensor ocean bottom receivers(OBC/OBN)is becoming increasingly widespread.As a key technology in dual-sensor data processing,the separation of the up-going and down-going wavefields determines the data processing quality and ap⁃plication effectiveness.To address the limitations of conventional methods that fail to separate the up-going and down-going wavefields,hydrophone and geophone seismic data are utilized in the frequency-wavenumber domain.By calculating the calibration filter factor for both types of data,with and without direct waves,precise calibration and effective separation of the up-going and down-going wavefields are achieved.The separated up-going wave⁃field data not only eliminates interference from multiple ghost waves but also improves the signal-to-noise ratio and resolution of seismic data.It thus provides high-fidelity up-going and down-going wavefield data for subsequent joint deconvolution and migration imaging processes.The data examples demonstrate the effectiveness and practical⁃ity of the proposed method.