Imaging Attenuation From Array Analysis of Surface Waves

Bao, Xueyang1,2,3; Wang, Nian4

2024-09-01

10.1029/2023JB028649

JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH   影响因子和分区

2169-9313

2169-9356

["Anelastic attenuation provides key insight in our understanding of thermal and rheological structures and the associated deformation and dynamic mechanisms of the Earth's deep interior. Unfortunately, attenuation tomography is advanced far behind wave-speed tomography due to the challenge in properly excluding the complex effects of elastic heterogeneities on seismic wave amplitude. By taking advantage of phase tracking in seismic array analysis, here we derive a new theory of Helmholtz tomography that well accounts for attenuation, source radiation, and scattering, etc., and present a technique called Helmholtz Multi-Event Tomography (HelMET) to retrieve the attenuation properly. The effectiveness of this method is then validated by synthetic inversions. Our synthetic seismograms are calculated using a newly developed three-dimensional finite-difference algorithm that accounts for physical dispersion and dissipation in anelastic media and remains accurate and stable even if strong attenuation exists. Compared to the traditional method poorly performed in the synthetic inversion, the HelMET well recovers the input attenuation anomalies, suggesting that this method can be used to successfully isolate attenuation from the complicated effects of elastic heterogeneities. Our results underline the implication of the new theory and method in accurately imaging high-resolution attenuation structures and unambiguously interpreting the anelastic heterogeneities of the Earth by array-based earthquake and ambient noise data with inexpensive computation.","Modeling attenuation from seismic-wave amplitude records is important for understanding the temperature structures and dynamic features of the Earth's interior. But it is still challenging to robustly image attenuation because wave amplitudes are also influenced by other factors besides attenuation, particularly the so-called scattering due to the complex effects of three-dimensional wave-speed and density distributions. Based on tracking surface-wave travel times and amplitudes from seismic array data, here we upgrade the theory of Helmholtz tomography by accounting for the scattering effects. We then present a new method, named as Helmholtz Multi-Event Tomography, for correctly solving for attenuation structures. We carry out synthetic inversions to verify the new theory and new method. We perform three-dimensional forward simulations for seismic wave propagation in anelastic media. Our new method well recovers all input anomalies of attenuation, while the performance of traditional imaging is typically poor for various input models. Our results demonstrate the effectiveness of the new theory and new method in solving for attenuation structures. We prospect the new theory and new method are promising to generate accurate and precise models of attenuation from real data with low computational cost.","We upgrade the theory of surface-wave Helmholtz tomography that accounts for attenuation, source radiation, and scattering effects We present a new method to isolate attenuation from array-based surface-wave phase and amplitude measurements Synthetic inversions show that our method well recovers the input attenuation structure, yet the traditional method poorly performs"]

SCI

英语

第一 ; 通讯

Guangdong Provincial Key Laboratory of Geophysical High-resolution Imaging Technology[2022B1212010002] ; Project for introduced Talents Team of Southern Marine Science and Engineering Guangdong (Guangzhou)[GML2019ZD0203] ; China Postdoctoral Science Foundation[2021M690087] ; High level special funds[G03050K001] ; null[42204056]

Geochemistry & Geophysics

Geochemistry & Geophysics

WOS:001314241700001

AMER GEOPHYSICAL UNION

Web of Science

1.Southern Univ Sci & Technol, Dept Earth & Space Sci, Shenzhen, Peoples R China
2.Southern Univ Sci & Technol, Guangdong Prov Key Lab Geophys High Resolut Imagin, Shenzhen, Peoples R China
3.Southern Marine Sci & Engn Guangdong Lab Guangzhou, Guangzhou, Peoples R China
4.Tsinghua Univ, Dept Mathemet Sci, Beijing, Peoples R China

Bao, Xueyang,Wang, Nian. Imaging Attenuation From Array Analysis of Surface Waves[J]. JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH,2024,129(9).

Bao, Xueyang,&Wang, Nian.(2024).Imaging Attenuation From Array Analysis of Surface Waves.JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH,129(9).

Bao, Xueyang,et al."Imaging Attenuation From Array Analysis of Surface Waves".JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH 129.9(2024).