基于尖脉冲子波的高分辨率气枪震源设计OA北大核心CSTPCD

The optimization design of high-resolution air gun source is crucial to offshore hydrocarbon exploration.According to the relationship between source wavelet form and seismic resolution,the spike wavelet is used as the basis for source optimization.Based on wavelet simulation for different air gun capacities using a wavelet model in non-ideal gas conditions,quantitative analysis is performed on the peak value of the main pulse and the time to reach the peak for different air gun capacities.Thus,a spike wave-let is constructed by adjusting the delayed excitation time and setting depth of air guns with different capacities in the array to a-chieve in-phase stacking of main pulse peaks.We design two kinds of spike-wavelet air gun arrays on the basis of conventional ar-rays and investigate their wavelets and spectra.The results show that spike-wavelet arrays perform better than conventional arrays in suppressing ghost reflections and trapped waves.Main peak value,peak-to-peak difference and amplitude ratio of the first pres-sure pulse to the first bubble pulse increase by 11.6％,12.4％and 16.4％,respectively.Both high frequencies and low frequencies are expanded;the effective bandwidth is increased by 14.5％;more energy could travel downward to improve signal-to-noise ratio and resolution.