Under the layer tuning effects,the interference patterns are changing with different offsets of seismic reflections and,as a result,the amplitude and frequency information is distorted,and this will worsen the confidence and resolution of the AVO/AVA analysis and inversion.Firstly,the authors gave the seismic reflection equations with tuning effects,with the modeling examples illustrating characteristics of the tuned seismic gather.Secondly,in consideration of the different detuning levels caused by the changing layer-thickness,the authors constructed the self-adaptive non-stationary decomposition via local Lamoureux time window.Finally,the authors built the non-stationary cost function for matching seismic angle gather to correct the amplitude and waveform stretch.Field application demonstrates the feasibility of the proposed method in improving the quality of seismic data with larger angle,with the high-quality data causing the success of reservoir prediction and hydrocarbon identification.