Geology-target-oriented High-dimensional Phase Attributes And Application On The Wide-azimuth Seismic Data

Phase is sensitive to the discontinuities of the subsurface structural and stratigraphic anomalies,but lack of robustness when dealing with noisy data.In addition,phaseassociated variation among different azimuths is seldom considered.Currently seismic exploration targets typically involve complex combinations of the subsurface varyingscale geologic anomalies with different vertical and lateral distributions.The conventional methods for measuring the discontinuities based on broadband poststack seismic data always overlap the information of the frequencies,overlap the discontinuities along different trends,and stack the azimuthal anisotropy.To address the issues above,we present six-dimensional(6D)phase attributes derived from azimuthal phase-frequency spectra to measure the discontinuities as well as to indicate the azimuthal variation,under the guidance of geologic targets including thickness,trend and dip.Through the increased trend?frequency and azimuth dimensions,the 6D phase attributes contain plentiful information of the geological anomalies of different scales.In addition,to improve the calculation efficiency,the high-dimensional phase-difference cross-correlation attribute is also proposed in this paper.A simple addition and subtraction operation between adjacent phase traces is adopted to replace the multi-traces addition and multiplication operation in the 6D phase attributes.Moreover,we provide q-value attributes to approximately describe the variation intensity of phase attributes among different azimuths,and to attempt to indicate the anisotropy.Five seismic datasets involving a synthetic model,a wide-azimuth physical modeling dataset,a poststack real dataset and two wide-azimuth real datasets are adopted to illustrate the performances of the proposed high-dimension phase attributes and the derived q-value attributes.The results show that phase attributes at different frequencies can image different deep geological features,including the channels,the faults of different scales,fracture groups of different scales and karst caves.In addition,the phase attributes among different azimuths and the q-value attributes can indicate the azimuthal variations,and to further indicate the anisotropy.Especially,some detected karst caves are clearly observed to be connected in phase attributes at only one large azimuth angle.The proposed 6D phase attributes can be therefore used as a potential tool for wideazimuth seismic data interpretation.