{"title":"二维弹性介质中的双差约束反射断层成像","authors":"Kai Zhang, Haotian Yang, Zhenchun Li, Min Hu","doi":"10.1111/1365-2478.13512","DOIUrl":null,"url":null,"abstract":"<p>The inverted velocity model obtained from the reflection tomography based on the angle domain common-image gathers has a certain fuzziness. The inverted velocity model's stratigraphic interface is always not clear enough in areas with complex stratigraphic structure. In order to improve the accuracy and resolution of the inverted velocity model, a double-difference constraint condition is added on the basis of minimizing the absolute travel-time residual at the subsurface imaging points. This constraint makes the inverted velocity model local structure information more refined by minimizing the differential travel-time residual at adjacent imaging points (i.e. closely spaced points within the same layer) and makes the variation of velocity model information within a certain range more accurate. The method in this paper is based on angle domain common-image gathers, the tomography inversion equation is established by using the ray tracing method, and the conversion relationship between the traveltime residual and the residual curvature of the angle domain common-image gathers. Then, by adding differential constraint and double-differential constraint conditions and using the least squares QR decomposition method to solve the set of equations, the inverted velocity model can be obtained through multiple iterations, which provides a high-precision velocity field for the migration and improves the accuracy of seismic imaging. Numerical experiments on both one typical model and a field data example demonstrate the effectiveness of the proposed double-difference constrained elastic reflection tomography in generating high-precision velocity models.</p>","PeriodicalId":12793,"journal":{"name":"Geophysical Prospecting","volume":null,"pages":null},"PeriodicalIF":1.8000,"publicationDate":"2024-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Double-difference constrained reflection tomography in two-dimensional elastic media\",\"authors\":\"Kai Zhang, Haotian Yang, Zhenchun Li, Min Hu\",\"doi\":\"10.1111/1365-2478.13512\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p>The inverted velocity model obtained from the reflection tomography based on the angle domain common-image gathers has a certain fuzziness. The inverted velocity model's stratigraphic interface is always not clear enough in areas with complex stratigraphic structure. In order to improve the accuracy and resolution of the inverted velocity model, a double-difference constraint condition is added on the basis of minimizing the absolute travel-time residual at the subsurface imaging points. This constraint makes the inverted velocity model local structure information more refined by minimizing the differential travel-time residual at adjacent imaging points (i.e. closely spaced points within the same layer) and makes the variation of velocity model information within a certain range more accurate. The method in this paper is based on angle domain common-image gathers, the tomography inversion equation is established by using the ray tracing method, and the conversion relationship between the traveltime residual and the residual curvature of the angle domain common-image gathers. Then, by adding differential constraint and double-differential constraint conditions and using the least squares QR decomposition method to solve the set of equations, the inverted velocity model can be obtained through multiple iterations, which provides a high-precision velocity field for the migration and improves the accuracy of seismic imaging. Numerical experiments on both one typical model and a field data example demonstrate the effectiveness of the proposed double-difference constrained elastic reflection tomography in generating high-precision velocity models.</p>\",\"PeriodicalId\":12793,\"journal\":{\"name\":\"Geophysical Prospecting\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":1.8000,\"publicationDate\":\"2024-04-08\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Geophysical Prospecting\",\"FirstCategoryId\":\"89\",\"ListUrlMain\":\"https://onlinelibrary.wiley.com/doi/10.1111/1365-2478.13512\",\"RegionNum\":3,\"RegionCategory\":\"地球科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"GEOCHEMISTRY & GEOPHYSICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Geophysical Prospecting","FirstCategoryId":"89","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1111/1365-2478.13512","RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"GEOCHEMISTRY & GEOPHYSICS","Score":null,"Total":0}
引用次数: 0
摘要
基于角域共像采集的反射层析成像得到的反演速度模型具有一定的模糊性。在地层结构复杂的地区,反演速度模型的地层界面总是不够清晰。为了提高反演速度模型的精度和分辨率,在最小化地下成像点绝对旅行时间残差的基础上,增加了双差分约束条件。该约束条件通过最小化相邻成像点(即同一层内间隔较近的点)的差分旅行时间残差,使反演的速度模型局部结构信息更加精细,并使速度模型信息在一定范围内的变化更加精确。本文的方法基于角域共像采集,利用射线追踪法建立层析成像反演方程,并建立走时残差与角域共像采集残差曲率之间的转换关系。然后,加入微分约束和双微分约束条件,利用最小二乘 QR 分解法求解方程组,通过多次迭代得到反演速度模型,为迁移提供了高精度的速度场,提高了地震成像的精度。一个典型模型和一个野外数据实例的数值实验证明了所提出的双差分约束弹性反射层析技术在生成高精度速度模型方面的有效性。
Double-difference constrained reflection tomography in two-dimensional elastic media
The inverted velocity model obtained from the reflection tomography based on the angle domain common-image gathers has a certain fuzziness. The inverted velocity model's stratigraphic interface is always not clear enough in areas with complex stratigraphic structure. In order to improve the accuracy and resolution of the inverted velocity model, a double-difference constraint condition is added on the basis of minimizing the absolute travel-time residual at the subsurface imaging points. This constraint makes the inverted velocity model local structure information more refined by minimizing the differential travel-time residual at adjacent imaging points (i.e. closely spaced points within the same layer) and makes the variation of velocity model information within a certain range more accurate. The method in this paper is based on angle domain common-image gathers, the tomography inversion equation is established by using the ray tracing method, and the conversion relationship between the traveltime residual and the residual curvature of the angle domain common-image gathers. Then, by adding differential constraint and double-differential constraint conditions and using the least squares QR decomposition method to solve the set of equations, the inverted velocity model can be obtained through multiple iterations, which provides a high-precision velocity field for the migration and improves the accuracy of seismic imaging. Numerical experiments on both one typical model and a field data example demonstrate the effectiveness of the proposed double-difference constrained elastic reflection tomography in generating high-precision velocity models.
期刊介绍:
Geophysical Prospecting publishes the best in primary research on the science of geophysics as it applies to the exploration, evaluation and extraction of earth resources. Drawing heavily on contributions from researchers in the oil and mineral exploration industries, the journal has a very practical slant. Although the journal provides a valuable forum for communication among workers in these fields, it is also ideally suited to researchers in academic geophysics.