Computation and analysis of surface wave dispersion and attenuation in layered viscoelastic-vertical transversely isotropic media by the generalized R/T coefficient method

Yuan, Shichuan1,2,3; Pan, Lei1; Shi, Caiwang1; Song, Xianhai4; Chen, Xiaofei1,2,3

2024-07-18

10.1093/gji/ggae207

GEOPHYSICAL JOURNAL INTERNATIONAL   影响因子和分区

0956-540X

1365-246X

In this study, we propose a systematic and effective method, that is, an extended version of the generalized reflection/transmission (R/T) coefficient method, for computing the phase-velocity (${c}_r$) dispersion curves, attenuation coefficient ($\alpha $) curves, and eigenfunctions of both Rayleigh and Love waves as well as the ellipticity of Rayleigh waves in layered viscoelastic-vertical transversely isotropic (VTI) media. The numerical scheme of combining the root-searching method with the local optimization method is designed for determining the complex-valued modal solutions (i.e. complex wavenumber $k = {\omega {/ {\vphantom {\omega {{c}_r - i\alpha }}}} {{c}_r - i\alpha }}$) of surface waves. The near-surface sedimentary geological environment is taken as the model example because it is typical viscoelastic-VTI media. Besides the anisotropic-viscoelastic (AV) media, our algorithm can also compute surface waves in isotropic-elastic (IE), isotropic-viscoelastic (IV) and anisotropic-elastic (AE) media by resetting the corresponding parameters. Using the six-layer half-space models and in these four media, we verify the correctness of our algorithm by benchmarking the modal solutions against those from other methods. In the four-layer half-space model, by comparing the results of IE, IV, AE and AV media, we analyse the effects of velocity anisotropy, viscoelasticity and attenuation anisotropy on the dispersion and attenuation characteristics of both Rayleigh and Love waves in detail. Our study can provide a theoretical basis and useful tool for surface wave imaging considering the anisotropy and/or viscoelasticity of the medium, which has the potential to better investigate the solid Earth's internal structure.

Elasticity and anelasticity Seismic anisotropy Seismic attenuation Surface waves and free oscillations

SCI ; EI

英语

第一 ; 通讯

National Natural Science Foundation of China["42304065","42304066","92155307","U1901602","42074164"] ; National Natural Science Foundation of China[KQTD20170810111725321] ; Shenzhen Science and Technology Innovation Program[2022B1212010002] ; Guangdong Provincial Key Laboratory of Geophysical High-resolution Imaging Technology[ZDSYS20190902093007855] ; Shenzhen Key Laboratory of Deep Offshore Oil and Gas Exploration Technology[2022M721460]

Geochemistry & Geophysics

Geochemistry & Geophysics

WOS:001270847400002

OXFORD UNIV PRESS

20243016751273

Anisotropy ; Dispersion (waves) ; Eigenvalues and eigenfunctions ; Geometry ; Numerical methods ; Seismology ; Viscoelasticity

Earthquake Measurements and Analysis:484.1 ; Mathematics:921 ; Numerical Methods:921.6 ; Physical Properties of Gases, Liquids and Solids:931.2

GEOSCIENCES

Web of Science

1.Southern Univ Sci & Technol, Dept Earth & Space Sci, Shenzhen 518055, Peoples R China
2.Southern Univ Sci & Technol, Shenzhen Key Lab Deep Offshore Oil & Gas Explorat, Shenzhen 518055, Peoples R China
3.Southern Univ Sci & Technol, Guangdong Prov Key Lab Geophys High Resolut Imagin, Shenzhen 518055, Peoples R China
4.China Univ Geosci, Sch Geophys & Geomat, Wuhan 430074, Peoples R China

Yuan, Shichuan,Pan, Lei,Shi, Caiwang,et al. Computation and analysis of surface wave dispersion and attenuation in layered viscoelastic-vertical transversely isotropic media by the generalized R/T coefficient method[J]. GEOPHYSICAL JOURNAL INTERNATIONAL,2024,238(3):1505-1529.

Yuan, Shichuan,Pan, Lei,Shi, Caiwang,Song, Xianhai,&Chen, Xiaofei.(2024).Computation and analysis of surface wave dispersion and attenuation in layered viscoelastic-vertical transversely isotropic media by the generalized R/T coefficient method.GEOPHYSICAL JOURNAL INTERNATIONAL,238(3),1505-1529.

Yuan, Shichuan,et al."Computation and analysis of surface wave dispersion and attenuation in layered viscoelastic-vertical transversely isotropic media by the generalized R/T coefficient method".GEOPHYSICAL JOURNAL INTERNATIONAL 238.3(2024):1505-1529.