Japan Geoscience Union Meeting 2022

Presentation information

[J] Poster

S (Solid Earth Sciences ) » S-TT Technology & Techniques

[S-TT40] Seismic Big Data Analysis Based on the State-of-the-Art of Bayesian Statistics

Mon. May 30, 2022 11:00 AM - 1:00 PM Online Poster Zoom Room (24) (Ch.24)

convener:Hiromichi Nagao(Earthquake Research Institute, The University of Tokyo), convener:Aitaro Kato(Earthquake Research Institute, the University of Tokyo), Keisuke Yano(The Institute of Statistical Mathematics), convener:Takahiro Shiina(National Institute of Advanced Industrial Science and Technology), Chairperson:Takahiro Shiina(National Institute of Advanced Industrial Science and Technology), Hiromichi Nagao(Earthquake Research Institute, The University of Tokyo)

11:00 AM - 1:00 PM

[STT40-P04] Proposal of Seismic Wavefield Reconstruction Method based on Data-Driven Reduced-Order Model and Sparse Observation

*Takayuki Nagata1, Kumi Nakai1, Keigo Yamada1, Yuji Saito1, Taku Nonomura1, Masayuki Kano1, Shin-ichi Ito2, Hiromichi Nagao2 (1.Tohoku University, 2.Earthquake Research Institute, The University of Tokyo)

Keywords:Seismic wavefield reconstruction, Data-driven science, Reduced-order model, Compressed sensing

In the present study, we propose a low-cost and high-accuracy seismic wavefield reconstruction method based on a data-driven reduced-order model and sparse observation.
The proposed method consists of a model construction phase and an observation/reconstruction phase. In the model construction phase, a large number of simulations in which the parameters are randomly changed are conducted for an earthquake that occurs in a certain hypocentral region, and a data-driven reduced-order model is constructed from the obtained data set. In the observation/reconstruction phase, a spatially continuous wavefield is estimated using the observed waveform at the observation sites and the reduced-order model constructed in advance. In addition, when it is necessary to reduce the number of observation points used for reconstruction to reduce the calculation cost or confirm the soundness of the reconstruction data, a selection of observation sites using the greedy method based on the design of experiments is available. Numerical experiments were conducted on the horizontal stratified structure with three layers, and it was shown that the seismic wavefield can be reconstructed at a low cost and with high accuracy.