反演(地质)
质点速度
声波方程
合成数据
地质学
反变换采样
模态色散
群速度
算法
表面波
大地测量学
波传播
声学
光学
物理
计算机科学
地震学
光纤传感器
光纤
构造学
色散位移光纤
作者
Jing Li,Hui Liu,Yibo Wang
摘要
Abstract Distributed acoustic sensing (DAS) is a new dense sampling seismic observation technique rapidly developed to image near‐surface velocity structures. Compared with traditional seismometer surveys, DAS can record the strain rate data with a high spatial and temporal resolution and low maintenance cost observation. However, the strain variation recorded by the DAS system is the horizontal component with a low signal‐to‐noise ratio because the coupling between the fiber and the earth is poor. In addition, conventional velocity inversion algorithms such as 1D dispersion curve inversion and 2D/3D full‐waveform inversion (FWI) are developed for particle velocity components. Hence, their application in DAS strain‐rate data requires conversion to particle velocity data, which would bring some numerical error. In this work, we propose the DAS wave‐equation dispersion inversion (DAS‐WD) method to invert the S‐wave velocity model directly from DAS strain rate data. The WD method does not require 1D dispersion curve inversion layered assumptions and overcomes the problem that the FWI is challenging to converge because the recorded horizontal DAS component data is noisy. Meanwhile, the strain rate DAS‐WD theory avoids the error caused by velocity and strain rate conversion by scaling of apparent velocity followed by time integrations. The typical synthetic and offshore DAS field data demonstrate that the proposed DAS‐WD method has great potential for a high‐resolution velocity tomogram.
科研通智能强力驱动
Strongly Powered by AbleSci AI