物探与化探2026，Vol.50Issue(3)：516-524,9.DOI:10.11720/wtyht.2026.1437
两种回转波FWI方法对比研究和应用
Comparative study and application of two FWI methods for turning waves
摘要
Abstract
Currently,full-waveform inversion(FWI)represents the velocity inversion and modeling technology with the highest accura-cy.By continuously updating the velocity model through an iterative algorithm,FWI gradually minimizes the errors between forward modeling data and real data,thereby approaching the true velocity model.The primary challenge faced by FWI is cycle skipping,which occurs when the phase difference between forward modeling data and real data exceeds half a cycle.In this case,with the updating of the velocity model,the forward modeling data and real data will be incorrectly matched,causing the velocity model to converge in a wrong direction.In conventional least-squares FWI,the objective function considers merely the energy difference between forward modeling data and real data.In this case,cycle skipping can only be avoided as far as possible by using the low-frequency signals with high cycles in the data and a sufficiently accurate initial velocity model.This poses stringent demands for the quality of low-frequency signals in raw data and entails a substantial workload for the initial velocity modeling.To address this issue,this study proposes a time-lag FWI(TLFWI)method.In this method,the objective function is defined as the integral of the energy difference between forward modeling da-ta and real data with respect to their time difference.In this manner,the objective function accounts for both the energy difference and time difference between forward modeling data and real data,enabling cycle skipping to be effectively avoided.In the case of weak low-frequency signals in raw data and large errors in the initial velocity model,TLFWI can still enable the velocity model to converge in the correct direction.Therefore,TLFWI reduces the dependence on low-frequency signals in raw data and decreases the workload for con-structing the initial velocity model.The results of experiments on a theoretical velocity model and practical seismic data reveal that,com-pared to least-squares FWI,TLFWI can derive a more accurate velocity model under the condition of high errors in the initial velocity model.Notably,both least squares FWI and TLFWI used in this study are turning wave FWI.In other words,only turning waves in seis-mic data are used for matching in both methods,with reflected waves excluded.关键词
回转波时延全波形反演/回转波最小二乘全波形反演/跳周现象/低频信号/初始速度模型/深度偏移Key words
turning wave time-lag full-waveform inversion(FWI)/turning wave least-squares FWI/cycle skipping/low-frequency sig-nal/initial velocity model/depth migration分类
天文与地球科学引用本文复制引用
王丙钢,丁成震,吴建鲁,李翔,董庆宇,张丹..两种回转波FWI方法对比研究和应用[J].物探与化探,2026,50(3):516-524,9.基金项目
中国石油天然气股份有限公司重大科技专项资助(2021-DJ-34-01) （2021-DJ-34-01）
