| 摘要 |
Methods of processing seismic data to remove unwanted noise from meaningful reflection signals are provided for. The seismic data is transformed from the offset-time domain to the time-slowness domain using a Radon transformation. Preferably, the Radon transformation is applied within defined slowness limits pmin, and pmax, where pmin is a predetermined minimum slowness and pmax is a predetermined maximum slowness, and an offset weighting factor x<n> is applied to the amplitude data, wherein 0 < n < 1. A high resolution Radon transformation preferably is used, where the transformation is performed according to an index j of the slowness set and a sampling variable Delta p; wherein Formula (1) Deltap is from about 0.5 to about 4.0 µsec/m, pmax, is a predetermined maximum slowness, and pmin is a predetermined minimum slowness. A high-low, preferably a time variant, high low corrective filter is then applied to enhance the primary reflection signal content of the data and to eliminate unwanted noise events. The tau-P filter is defined by reference to the velocity function of the primary reflection signals, and preferably is expressed as: Formula (2) where r1 , and r2 are percentages expressed as decimals. The slowness limits typically are set within ± 15% of the velocity function, and r1, and r2 may be set accordingly. After filtering, the enhanced signal content is inverse transformed from the time-slowness domain back to the offset-time domain using an inverse Radon transformation. |
