Imaging shallow structure with active-source surface wave signal recorded by distributed acoustic sensing arrays |
| |
| Authors: | Zhenghong Song Xiangfang Zeng Clifford H Thurber Hebert F Wang Dante Fratta |
| |
| Affiliation: | 1.School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China2.State Key Laboratory of Geodesy and Earth’s Dynamics, Institute of Geodesy and Geophysics, Chinese Academy of Science, Wuhan 430077, China3.Department of Geoscience, University of Wisconsin-Madison, Madison, WI 53706, USA4.Geological Engineering, Department of Civil and Environmental Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA |
| |
| Abstract: | Distributed acoustic sensing (DAS) is one recently developed seismic acquisition technique that is based on fiber-optic sensing. DAS provides dense spatial spacing that is useful to image shallow structure with surface waves. To test the feasibility of DAS in shallow structure imaging, the PoroTomo team conducted a DAS experiment with the vibroseis truck T-Rex in Brady’s Hot Springs, Nevada, USA. The Rayleigh waves excited by the vertical mode of the vibroseis truck were analyzed with the Multichannel Analysis of Surface Waves (MASW) method. Phase velocities between 5 and 20 Hz were successfully extracted for one segment of cable and were employed to build a shear-wave velocity model for the top 50 meters. The dispersion curves obtained with DAS agree well with the ones extracted from co-located geophones data and from the passive source Noise Correlation Functions (NCF). Comparing to the co-located geophone array, the higher sensor density that DAS arrays provides help reducing aliasing in dispersion analysis, and separating different surface wave modes. This study demonstrates the feasibility and advantage of DAS in imaging shallow structure with surface waves. |
| |
| Keywords: | distributed acoustic sensing surface wave multiple channel analysis shallow structure |
|
| 点击此处可从《Earthquake Science》浏览原始摘要信息 |
|
点击此处可从《Earthquake Science》下载全文 |
|
