TY - JOUR
T1 - The origin of secondary microseism Love waves
AU - Gualtieri, Lucia
AU - Bachmann, Etienne
AU - Simons, Frederik J
AU - Tromp, Jeroen
N1 - KAUST Repository Item: Exported on 2022-06-14
Acknowledged KAUST grant number(s): OSR-2016-CRG5-2970-01
Acknowledgements: We thank Congyue Cui for running numerical simulations on the supercomputer Summit at the Oak Ridge National Laboratory, Bernhard Schuberth for helping with the implementation of the rotation of the motion in SPECFEM3D GLOBE, and Fabrice Ardhuin for making available the output of the ocean wave model. We thank the two anonymous reviewers for their comments, which greatly improved our manuscript. Plotting and data analysis made use of MATLAB. This research used resources of the Oak Ridge Leadership Computing Facility, which is a US Department of Energy Office of Science User Facility supported under contract DE-AC05-00OR22725. Additional computational resources were provided by the Princeton Institute for Computational Science & Engineering. We thank Tariq Alkhalifah and acknowledge funding from King Abdullah University of Science and Technology, grant OSR-2016-CRG5-2970-01.
This publication acknowledges KAUST support, but has no KAUST affiliated authors.
PY - 2020/11/9
Y1 - 2020/11/9
N2 - The interaction of ocean surface waves produces pressure fluctuations at the seafloor capable of generating seismic waves in the solid Earth. The accepted mechanism satisfactorily explains secondary microseisms of the Rayleigh type, but it does not justify the presence of transversely polarized Love waves, nevertheless widely observed. An explanation for two-thirds of the worldwide ambient wave field has been wanting for over a century. Using numerical simulations of global-scale seismic wave propagation at unprecedented high frequency, here we explain the origin of secondary microseism Love waves. A small fraction of those is generated by boundary force-splitting at bathymetric inclines, but the majority is generated by the interaction of the seismic wave field with three-dimensional heterogeneity within the Earth.We present evidence for an ergodic model that explains observed seismic wave partitioning, a requirement for full-wave field ambient-noise tomography to account for realistic source distributions.
AB - The interaction of ocean surface waves produces pressure fluctuations at the seafloor capable of generating seismic waves in the solid Earth. The accepted mechanism satisfactorily explains secondary microseisms of the Rayleigh type, but it does not justify the presence of transversely polarized Love waves, nevertheless widely observed. An explanation for two-thirds of the worldwide ambient wave field has been wanting for over a century. Using numerical simulations of global-scale seismic wave propagation at unprecedented high frequency, here we explain the origin of secondary microseism Love waves. A small fraction of those is generated by boundary force-splitting at bathymetric inclines, but the majority is generated by the interaction of the seismic wave field with three-dimensional heterogeneity within the Earth.We present evidence for an ergodic model that explains observed seismic wave partitioning, a requirement for full-wave field ambient-noise tomography to account for realistic source distributions.
UR - http://hdl.handle.net/10754/679001
UR - http://www.pnas.org/lookup/doi/10.1073/pnas.2013806117
UR - http://www.scopus.com/inward/record.url?scp=85096883134&partnerID=8YFLogxK
U2 - 10.1073/pnas.2013806117
DO - 10.1073/pnas.2013806117
M3 - Article
C2 - 33168742
SN - 1091-6490
VL - 117
SP - 29504
EP - 29511
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
IS - 47
ER -