HUSCAP logo Hokkaido Univ. logo

Hokkaido University Collection of Scholarly and Academic Papers >
Graduate School of Science / Faculty of Science >
Peer-reviewed Journal Articles, etc >

Detailed S-wave velocity structure of sediment and crust off Sanriku, Japan by a new analysis method for distributed acoustic sensing data using a seafloor cable and seismic interferometry

Files in This Item:

The file(s) associated with this item can be obtained from the following URL: https://doi.org/10.1186/s40623-022-01652-z


Title: Detailed S-wave velocity structure of sediment and crust off Sanriku, Japan by a new analysis method for distributed acoustic sensing data using a seafloor cable and seismic interferometry
Authors: Fukushima, Shun Browse this author
Shinohara, Masanao Browse this author →KAKEN DB
Nishida, Kiwamu Browse this author →KAKEN DB
Takeo, Akiko Browse this author →KAKEN DB
Yamada, Tomoaki Browse this author →KAKEN DB
Yomogida, Kiyoshi Browse this author →KAKEN DB
Keywords: S-wave velocity structure
Sediment and upper crust
Distributed acoustic sensing
Seismic interferometry
Seafloor cable
Frequency-wavenumber filter
Issue Date: 13-Jun-2022
Publisher: Springer
Journal Title: Earth planets and space
Volume: 74
Issue: 1
Start Page: 92
Publisher DOI: 10.1186/s40623-022-01652-z
Abstract: The S-wave velocity (Vs) structure of sediments and the uppermost crust in the landward slope of a subduction zone are important for determining the dynamics of the overriding plate. Although distributed acoustic sensing (DAS) measurements have improved the horizontal resolution of Vs structure in marine areas, the estimations have been limited to the uppermost sedimentary layers. In the present study, we applied seismic interferometry to DAS data of 13 h duration to image the sedimentary and crustal structure offshore of Sanriku, Japan with a spatial horizontal resolution of 2.5 km and >3.0 km depth. We grouped the DAS data into 10 km long subarrays with 75% overlaps. We first applied a frequency-wavenumber filter to the DAS data to remove DAS instrumental noise and to allow effective extraction of surface waves from short-time records. We then applied a seismic interferometry method and estimated the phase velocities at each subarray. The estimated phase velocities of the fundamental-mode and first higher-mode Rayleigh waves were then used to determine one-dimensional Vs structures for each subarray. The resultant 2-D Vs structure was interpreted as representing sediments and crust. The upper sedimentary layers thicken seaward, while the entire sedimentary unit shows complex lateral variations in depth. The boundary between the sedimentary layers and the uppermost crust varies in depth from 1.8 to 6.8 km and is the deepest in the middle of the profile. Combining this result with the P-wave velocity (Vp) structure along the nearest survey line, determined in previous studies, allowed us to estimate Vp/Vs = 3.12, on average, for the lower sedimentary layers. Our method of applying seismic interferometry to marine DAS data broadens the techniques for estimating Vs and Vp/Vs structure of sedimentary layers and the upper crust across subduction zones. These results show that application of the frequency-wavenumber filtering and seismic interferometry to marine DAS data can estimate the Vs structure and the Vp/Vs structure, together with standard marine geophysical surveys of sedimentary layers and the upper crust across subduction zones.
Type: article
URI: http://hdl.handle.net/2115/86473
Appears in Collections:理学院・理学研究院 (Graduate School of Science / Faculty of Science) > 雑誌発表論文等 (Peer-reviewed Journal Articles, etc)

Export metadata:

OAI-PMH ( junii2 , jpcoar_1.0 )

MathJax is now OFF:


 

 - Hokkaido University