Common offset ground penetrating radar data inversion based on ray theory

• 作者: XUE Meiqi LIU Sixin LU Qi LI Hongqing WANG Yuanxin CHANG Xinghao RAN Limin ZHAO Yonggang LI Jianwei
• 来源期刊: 世界地质（英文版）
• 年，卷（期）: 2021,（2）
• 页码范围: 103-110
• 页数: 8页
• 语种: 英文
• DOI: 10.3969/j.issn.1673-9736.2021.02.05

摘要

The authors use the common offset ground penetrating radar ( GPR) data inversion based on ray the-ory to estimate interval velocity and to obtain the relative permittivity .In the ray-tracing based inversion , the in-put data are the offset distance between antennas , the velocity of the first layer , the pick-up amplitude and re-ference amplitude of each reflection layer .The thickness and velocity of each layer are calculated by this recur-sive method.Firstly, the horizontal homogeneous layered medium model is established , and the ideal inversion results are obtained .Subsequently , Monte Carlo method is used to establish a randomly undulating homogene-ous layered medium model .The common offset GPR data for the built geological model is then simulated by finite-difference time-domain ( FDTD) .It proved that this ray-tracing based inversion method is feasible for the horizontal layered geological model , even the layered geological model with random undulation .Undulation , re-presented by RMS height and CL (correlation length ), influences the inversion results .Finally, a more com-plex geological model--pinch-out model was established .In the pinch-out model , the pinch-out interface can be clearly identified , though there is a false anomaly , which will not significantly affect the identification of the un-derground medium structure .