摘要
地震波能量被吸收造成地震资料中气云区形成大片的反射"空白区",导致气云区实际地层的Q值难以准确估算,影响了通过Q值反演对气云区衰减能量进行补偿的效果。提出了一种基于广义S变换的时频域气云区地震补偿方法,首先通过广义S变换对地震数据进行分频处理,然后拟合各频段地震资料的衰减函数,最后分别在时间域、频率域对各频段地震资料进行补偿。该方法避免了对实际地层Q值的估算,克服了实际地层Q值求不准的难点。同时,通过引入广义S变换作为分频函数,有效避免了常规分频函数对地震数据分频精度不高的问题。该方法能够有效补偿由于气云吸收衰减作用造成的能量衰减。实际气云区地震资料处理振幅补偿效果较好,具有一定的工业应用价值。
The attenuation of seismic wave energy results in a large reflection "blank area" in the gas cloud area. It is difficult to accurately estimate the Q factor of the actual formation in the gas cloud area, which affects the compensation of the attenuation energy in the gas cloud area based on the Q factor inversion. In this paper, a compensation method in time-frequency domain based on generalized S-transform for seismic in gas cloud area is proposed. Firstly, the seismic data is divided into several frequency bands based on generalized S-transform. Secondly, the attenuation function of the seismic data is fitted corresponding to each frequency band. Finnally, the seismic amplitude compensation of each frequency band is compensated in the time-frequency domain respectively. This method avoids the estimation of the Q factor, which overcomes the difficulty of estimating accurate Q factor of the actual formation. Meanwhile, by introducing generalized S-transform as frequency-division function, the seismic data frequency division accuracy is effectively improved while comparing to that of conventional frequency-division function. Based on this method, seismic amplitude caused by gas cloud absorption and attenuation can be effectively compensated. This method is applied in real seismic data processing of gas cloud area, and it shows good amplitude compensation effect, which has certain industrial application value.
引文
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