初始模型和约束条件对层析反演结果的影响

The effects of initial velocity model and constraint values to tomographic results

南京地矿部石油物探研究所, 南京210014

Rcsearch Institute of Geophysical Prospecting for Petroleum, Nanjin8 210014

本文以一个多层层状介质数学模型、一个高速方块作物理模型及一个低速方块体物理模型为例,详细讨论了在以均匀初始速度模型、真实速度模型、与真实速度模型完全相反的初始速度模型、与真实速度模型相近的初始速度模型及有无约束等几种情况对反演结果的影响。通过对这些层析反演结果的分析对比,提出了在层析反演过程中如何构造初始速度模型的方法与建议。

Using a multi-layered mathematical model, a high velocity cube physical model and a lowvelocity cube physical model as examples,this paper presents detailed discussions on the effects ofdifferent initial velocity models such as a constant vclocity model,a vclocity model to be cqual tothe original velocity model, a velocity model of contrary velocity distributions to the originalvelocity model, and a velocity model with similar velocity distributions to the original velocitymodel, and constraint values to tomographic inversion results. Suggestions and methods on theconstruction of initial ve locity models at the beginning of tomographic inversion process were givenbased on the analysis of the results presented in the paper.