TY - JOUR
T1 - Estimation of Seismic Attenuation of the Greenland Ice Sheet Using 3-D Waveform Modeling
AU - Toyokuni, Genti
AU - Komatsu, Masanao
AU - Takenaka, Hiroshi
N1 - Funding Information:
The authors are grateful to Drs. Dean Childs, Kevin Nikolaus, Kent Anderson, Masaki Kanao, Yoko Tono, Seiji Tsuboi, Robin Abbott, Kathy Young, Drew Abbott, Silver Williams, Jason Hebert, Tetsuto Himeno, Susan Whitley, Orlando Leone, Akram Mostafanejad, Kirsten Arnell, Alissa Scire, and other staff members at GLISN, IRIS/PASSCAL, CH2M HILL Polar Services, and Norlandair for their contributions to the field operations in Greenland. The authors thank the staff of the IRIS/DMC for providing the open‐access waveform data used in this study. Dr. Yasmina M. Martos kindly provided the GHF data for Greenland. The authors appreciate Profs. Dapeng Zhao, Ryota Takagi, Akira Hasegawa, Hiroo Kanamori, and Katsutada Kaminuma for helpful discussions at the early stage of this study. This study was partially supported by research grants from the Japan Society for the Promotion of Science (Nos. 15K17742, 18K03794, 24403006, 23224012, 26282105, and 26241010). The GMT (Wessel et al., 2013 ) and SAC (Goldstein et al., 2003 ) software packages were used in this study.
Publisher Copyright:
© 2021. American Geophysical Union. All Rights Reserved.
PY - 2021/4
Y1 - 2021/4
N2 - We estimated the seismic attenuation (Q factor) of the Greenland Ice Sheet (GrIS) by comparing observed and theoretical Rayleigh waveforms. Observed waveforms are obtained by interfering noise waveforms in vertical-component seismograms between stations belonging to the latest broadband seismic network distributed throughout Greenland (GLISN network). Theoretical waveforms are calculated by parallel computation using the latest 3-D seismic waveform modeling method. Comparing the observed waveforms with the theoretical waveforms at different Q factors reveals that the GrIS has a low Q of 10 ≤ QP, QS ≤ 50, indicating very high attenuation of seismic waves due to the ice. This study is the first to establish the low Q factor of ice sheets via ultra-long-distance propagation (350−1,000 km). The Q factors obtained in this study are indispensable for estimating the thermal state and density distribution of the GrIS, as well as for interpreting the characteristics of seismic waveform that propagates through the GrIS.
AB - We estimated the seismic attenuation (Q factor) of the Greenland Ice Sheet (GrIS) by comparing observed and theoretical Rayleigh waveforms. Observed waveforms are obtained by interfering noise waveforms in vertical-component seismograms between stations belonging to the latest broadband seismic network distributed throughout Greenland (GLISN network). Theoretical waveforms are calculated by parallel computation using the latest 3-D seismic waveform modeling method. Comparing the observed waveforms with the theoretical waveforms at different Q factors reveals that the GrIS has a low Q of 10 ≤ QP, QS ≤ 50, indicating very high attenuation of seismic waves due to the ice. This study is the first to establish the low Q factor of ice sheets via ultra-long-distance propagation (350−1,000 km). The Q factors obtained in this study are indispensable for estimating the thermal state and density distribution of the GrIS, as well as for interpreting the characteristics of seismic waveform that propagates through the GrIS.
KW - 3-D modeling
KW - finite-difference method (FDM)
KW - Greenland Ice Sheet (GrIS)
KW - Greenland Ice Sheet Monitoring Network (GLISN)
KW - Q factor
KW - seismic attenuation
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U2 - 10.1029/2021JB021694
DO - 10.1029/2021JB021694
M3 - Article
AN - SCOPUS:85104929714
SN - 0148-0227
VL - 126
JO - Journal of Geophysical Research
JF - Journal of Geophysical Research
IS - 4
M1 - e2021JB021694
ER -