High Precision NMO And Stacking Technique Research And Application

Long-offset seismic signal processing has always been a difficulty in seismic data processing, Especially shallow long-offset seismic records, can hardly be real reacted after NMO correction. In order to maintain resolution, conventional practice is directly cut, leaving only high frequency signals in near offset. But we always want to retain long-offset signals as much as possible. This paper made a thorough study and summary, trying to improve long-offset NMO correction precision based on previous studies, truly reacted long-offset signals while maintaining the resolution at the same time, achieved good results. This paper also studied the High precision CMP stacking, for the purpose of improving the solvability of stacked section, achieved some results. Main contents:In-depth studied the current two branches of NMO correction:one by one move and block move. For the former, I studied the higher orders truncation and optimization of the normal NMO formula, translation Hyperbolic Correction which can more close to actual travel time, analyzed their accuracy at different offset to depth ratio. I also studied the generating mechanism of NMO stretching, tried to eliminate it based on different methods, achieved a certain effect. For the latter, I studied the initial Block Move Sum, developed Constant Moveout Correction and stretch free stacking.I purposed vertical sliding Optimization NMO correction based on these achievement, made satisfactory results through model test and real data processing.At last ,I studied high-precision smart stacking, removed unwanted noise and interference, highlight the effective signals. The numerical test and the actual data processing have made good results.