[S-TT42] Recent Advances in Exploration Geophysics 2019

[STT42-07] The observation of active source and ambient noise signals with telecommunication fiber-optic cable in urban area

*Baoshan Wang¹, Xiangfang Zeng², Xiaobin Li³, Weiwei Xu⁴, Shanhui Xu⁴, Zhenghong Song¹ (1.School of Earth and Space Sciences, University of Science and Technology of China, 2.State Key Laboratory of Geodesy and Earth’s Dynamics, Institute of Geodesy and Geophysics, Chinese Academy of Sciences, 3.Earthquake Agency of Yunnan Province, 4.Institute of Geophysics, China Earthquake Administration)

Keywords:Urban Area, Telecommunication Fiber-optic Cable, Seismic Monitoring

The Distributed Acoustic Sensing (DAS) is a rapidly developing technique, which can provide dense (~ meters) seismic observations. Recently, several experiments were performed using specifically deployed fiber-optic cables, while the seismic observation with telecommunication fiber-optic cable in urban area is still challenging. A 5.2 km long telecommunication fiber-optic cable buried at about 30-cm depth in urban area is used to record active source shots and more than 10-hours continuous ambient noise. We are able to extract seismic signals with the telecommunication fiber-optic cable 9 km from the active source (~Ml0.7). The high-frequency (~ 10 Hz) Rayleigh wave signal emerges from the noise cross-correlation functions. The dispersion information of Rayleigh wave is inverted for Vs at the top 30 m and construct a 2D profile, which helps to assess ground shaking in this area.