高斯波包散射体成像方法  

A scatterer imaging method based on Gaussian packet

作　　者：李辉[1] 殷俊锋[1] 王华忠[2] 刘守伟 刘太臣 

机构地区：[1]同济大学数学系,上海200092 [2]同济大学海洋与地球科学学院波现象与反演成像研究组,上海200092 [3]上海青凤致远地球物理地质勘探科技有限公司,上海200093

出　　处：《石油地球物理勘探》2017年第2期273-282,共10页Oil Geophysical Prospecting

基　　金：国家重大专项(2016ZX05024001-006和2016ZX05026001-003);国家自然科学基金面上项目(41274117)联合资助

摘　　要：在Gabor域描述散射体,且入射波场为短时宽带信号时,扰动波场可以在频率域用高斯束或在时间域用高斯波包描述。在此基础上,提出一种散射体成像方法,该方法对数据进行特征高斯波包分解,分解出的高斯波包独立反传,反传的高斯波包反投影到模型域得到一个Gabor函数描述的散射体(简称Gabor散射体)。将所有Gabor散射体叠加可以得到最终的成像结果。高斯波包散射体成像结果具有模型域的量纲,计算量较小且应用灵活。数值实验表明,本文提出的散射体成像方法精度较高,成像策略和流程适用于一般散射体。When perturbed model is described with Gabor frames, the scatter waves can be calculated with Gaussian beam in the frequency domain or Gaussian packet in the time domain. For this case the precondition is that signals of the incident background wave-field should be short-duration in the time domain and broad-band in the frequency domain. With the above-mentioned modeling method an effective scatterer imaging algorithm is put forward. A common-shot-gather is decomposed with characteristic Gaussian packet firstly. All of the Gaussian packets that describe the common-shot-gather are back-propagated and projected into the model domain independently. The final scatterer is obtained by integrating all of the Gabor-scatterers that projected from Gaussian packets. One of the scatterer imaging method's key points is how to project Gaussian packet into the model domain. The scatterer imaging method is composed by 3 parts of the imaging algorithm, the projection theory from a Gaussian packet to a Gabor-scatterer, and the back-propagation scheme of Gaussian packet. The proposed scatterer imaging method gives the image that has the dimension in the model domain. Gaussian packet shares higher efficiency and better flexibility compared with wave equation. The accuracy of the proposed scatterer inversion method is tested and analyzed with a single Gabor-scatterer model in the numerical experiment. The scatterer inversion scheme is also applied in synthetic models and promising results is presented. Both of the experiments show that the proposed method shares high efficiency, and the algorithm is suitable for general models. © 2017, Editorial Department OIL GEOPHYSICAL PROSPECTING. All right reserved.

关 键 词：高斯波包 扰动波场 散射体 成像 GABOR函数 

分 类 号：P631[天文地球—地质矿产勘探]