Phase information of seismic signals is sensitive to subsurface discontinuities. However, 1D phase attributes are not robust when dealing with noisy data. In addition, variations of seismic phase attributes with azimuth are seldom explored. To address these issues, we have developed 6D phase-difference attributes (PDAs) derived from azimuthal phase-frequency spectra. For the seismic volume of a certain azimuth and frequency, we first construct stacked phase traces at each common-depth point along a certain decomposed trending direction. Then, the 6D PDA is extracted by calculating the complex-valued covariance at a 6D phase space. The proposed method enables characterization of the subsurface discontinuities and indicates seismic anisotropy. Moreover, we provide one q-value attribute obtained by singular value decomposition to describe the variation intensity of PDA along different azimuths. Simulated and field wide-azimuth seismic data sets are used to illustrate the performance of the proposed 6D PDA and the derived q-value attribute. The results show that PDA at different frequencies can image various geologic features, including faults, fracture groups, and karst caves. Our field data example shows that PDA is able to discern the connectivity of karst caves using large-azimuth data. In addition, PDA along different azimuths and the q-value attribute provide a measurement of azimuthal variations, as well as the anisotropy. Our 6D PDA method can be used as a potential tool for wide-azimuth seismic data interpretation.

中文翻译：

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宽方位角地震数据解释的6D相差属性

地震信号的相位信息对地下不连续性敏感。但是，一维相位属性在处理嘈杂数据时并不稳健。此外，很少探讨地震相位属性随方位角的变化。为了解决这些问题，我们开发了从方位角相位频谱导出的6D相位差属性（PDA）。对于特定方位角和频率的地震量，我们首先沿某个分解趋势方向在每个公共深度点构造堆叠的相线。然后，通过计算6D相空间的复数值协方差来提取6D PDA。所提出的方法能够表征地下不连续面并指示地震各向异性。此外，我们提供一个q通过奇异值分解获得的值属性来描述PDA沿不同方位角的变化强度。使用模拟和野外广角地震数据集来说明所提出的6D PDA的性能和导出的q值属性。结果表明，不同频率的PDA可以成像各种地质特征，包括断层，裂缝组和岩溶洞穴。我们的现场数据示例表明，PDA可以使用大方位角数据来识别岩溶洞穴的连通性。另外，沿不同方位的PDA和q值属性可提供方位角变化以及各向异性的度量。我们的6D PDA方法可以用作宽方位角地震数据解释的潜在工具。