High resolution seismic refraction imaging of plate boundary structures by full waveform inversion off western Kii Peninsula, Nankai Trough

纪伊半岛西部、南海海槽全波形反演板块边界结构高分辨率地震折射成像

• 批准号: 22K20392
• 负责人: Qin Yanfang
• 金额: $ 1.83万
• 依托单位: Japan Agency for Marine-Earth Science and Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Research Activity Start-up
• 财政年份: 2022
• 资助国家: 日本
• 起止时间: 2022-08-31 至 2024-03-31
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-22K20392/
• 关键词: seismic inversion; full waveform; Nankai subduction zone; seismic; subsurface imaging; full waveform inversion; slow earthquake

As planned, I have obtained the starting model for full waveform inversion based on the first arrival travel time tomography. There are several things need to be prepared for application of the waveform inversion. First of all, the seismic data need to be preprocessed. Low signal to noise ratio of the original data bring in difficulties to the inversion and may cause artifacts. So I denoised the data properly. Another issue is the source wavelet for data modeling, which is a key for the inversion. I have tested several method to build up the source wavelet, and did the forward modeling by use each of them, respectively. After comparison, I chose the best one which can predict the first arrivals properly. After that, I need to design a strategy and run the inversion tests.

按计划，我根据首次到达旅行时间层析成像获得了全波形反演的启动模型。用于应用波形反演需要准备几件事。首先，需要预处理地震数据。原始数据的低信号与噪声比率给反转带来了困难，并可能导致伪影。因此，我正确地将数据降低了。另一个问题是用于数据建模的源波，这是反转的关键。我已经测试了几种构建源小波的方法，并分别通过使用每个方法进行了正向建模。比较后，我选择了可​​以正确预测第一个到达的最佳选择。之后，我需要设计策略并运行反转测试。

项目成果

The application of full waveform inversion in marine seismology: from industry to tectonics

全波形反演在海洋地震学中的应用：从工业到构造

• 发表时间: 2023
• 作者: Yanfang Qin

University Grenoble Alpes/Institut des Sciences de la Terre(フランス)

格勒诺布尔阿尔卑斯大学/大地科学研究所（法国）