Japan Geoscience Union Meeting 2023

Presentation information

[J] Online Poster

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

[S-TT42] Applying optic fiber sensing to earth science

Sun. May 21, 2023 1:45 PM - 3:15 PM Online Poster Zoom Room (7) (Online Poster)

convener:Eiichiro Araki(Japan Agency for Marine-Earth Science and Technology), Kentaro Emoto(Graduate School of Science, Kyushu University), Masatoshi Miyazawa(Disaster Prevention Research Institute, Kyoto University), Takeshi Tsuji(Department of Systems Innovation, the University of Tokyo)

On-site poster schedule(2023/5/21 17:15-18:45)

1:45 PM - 3:15 PM

[STT42-P06] Development of a Ground Monitoring Method Using Optical Fiber DAS and Microtremor Survey

*Hiroyuki Fujiwara1, Hiromitsu Nakamura1, Takashi Kunugi1, Shohei Naito1, Shigeki Senna1, Masato Sato1, Ken Sakurai2, Chisato Konishi2, Haruhiko Suzuki2, Masaki Takebe3 (1.National Research Institute for Earth Science and Disaster Resilience, 2.OYO Corporation, 3.Mitsubishi Electric Software Corporation)

Keywords:optical fiber, Distributed Acoustic Sensing, microtremor survey, ground

In order to develop a ground risk assessment method for sedimentary plains where large cities are located, we have started to develop a basic fundamental technology for high density, high precision, wide area detailed ground monitoring by integrating DAS (Distributed Acoustic Sensing) using optical fibers as sensors and microtremor surveys. Using existing optical fibers and seismic observation facilities, we are developing ground monitoring techniques using optical fiber DAS, establishing long-term continuous monitoring techniques, and developing analytical methods integrated with microtremor surveys and seismic wave interferometry.
NIED has developed various seismic observation networks, including K-NET, and has conducted microtremor surveys in specific areas, such as the Kanto region, to improve the accuracy of the 250m-mesh ground model. However, in some cases, amplification characteristics are underestimated and seismic motions are estimated to be small, so we have not adequately modeled the three-dimensional heterogeneous structure of the actual ground.
We will present an overview of the research project aimed at establishing fundamental techniques for high-density, high-precision, wide-area, detailed ground monitoring by combining optical fiber DAS and microtremor survey, and a comparison of ground vibration measurement performance using multiple types of optical fiber cables and interrogators in the test field.