【摘要】 全波形反演方法利用叠前地震波场的运动学和动力学信息重建地下速度结构,具有揭示复杂地质背景下构造与岩性细节信息的潜力.根据研究需要,全波形反演既可在时间域也可在频率域实现.频率域相对于时间域反演具有计算高效、数据选择灵活等优势.近十几年来频率域全波形反演理论在波场模拟方法、反演频率选择策略、目标函数设置方式、震源子波处理方式、梯度预处理方法等方面取得了进展.目标函数存在大量局部极值的特性是影响反射地震全波形反演效果的重要内在因素之一.如果将Laplace域波形反演、频率域阻尼波场反演、频率域波形反演三种方法有机结合,可以降低反演的非线性程度.更多还原

【Abstract】 The full waveform inversion (FWI) method utilizes the kinematic and dynamic information of prestack seismic data to rebuild underground velocity structure.It has the potential of revealing detailed structure and lithology characteristics under complex geological background.FWI can be carried out in the either frequency or time domain. Frequency-domain FWI has the advantages of high computation efficiency and data selection flexibility over its time-domain counterpart.Recent advances in frequency-domain FWI including waveform modeling methods,frequency selection strategies,object function configuration styles,source wavelet processing methods,and gradient precondition methods make it attractive for realistic problems.The multiple local minimal nature of the object function js one of the major obstacles to good reflection waveform inversion results.The frequency-domain damped wavefield inversion method fills the gap between the Laplace-domain and frequency-domain FWI methods.The combination of the three methods can mitigate the strong nonlinearity of the waveform inversion problem.更多还原