Finite-Frequency Delay Times of Phase Segments for Body Waves

Jiang, Yan1; Chen, Xiaofei2

2023-10-01

10.1785/0120220209

BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA   Impact Factor & Quartile

0037-1106

1943-3573

We propose a new way of measuring the delay times of body waves, based on the time differences between short segments of a phase. Using this proposed methodology, which we call the delay time of phase segments (DTPSs) method, we believe it is possible to (1) optimize the reduction mode that reduces finite-frequency kernels to ray-theoretical kernels, (2) reduce computation and memory storage costs by reducing the volume of finite -frequency sensitivity kernels, and (3) achieve greater linearity between delay times and velocity variations for larger velocity perturbations up to +/- 30%. The DTPS kernel can also be used in adjoint methods. Theory and our calculations indicate that the width of the DTPS kernel decreases as the length of the phase segment decreases from the length of the entire phase. The scattering caused by inhomogeneity is more likely to complicate the latter parts of a phase more than its beginning. For this reason, the DTPS method using a phase segment in the first quarter of a phase is robust for velocity perturbations up to +/- 30% from the initial model, whereas traditional methods using the entire phase are only robust for velocity perturbations up to +/- 10%. The DTPS method may reduce computation times by up to 70% because the size of the DTPS kernels is smaller than that of other methods by up to 70%. Synthetic tests indicate that the DTPS method produces inverse models nearly as accurate as generalized seismological data functionals.

SCI

English

Others

National Natural Science Foundation of China["U1839209","41790465","U1901602"] ; Shenzhen Key Laboratory of Deep Offshore Oil and Gas Exploration Technology[ZDSYS20190902093 007855]

Geochemistry & Geophysics

Geochemistry & Geophysics

WOS:001086144900002

SEISMOLOGICAL SOC AMER

GEOSCIENCES

Web of Science

1.China Earthquake Adm, Inst Geophys, Beijing, Peoples R China
2.Southern Univ Sci & Technol, Shenzhen Key Lab Deep Offshore Oil & Gas Explorat, Shenzhen, Peoples R China

Jiang, Yan,Chen, Xiaofei. Finite-Frequency Delay Times of Phase Segments for Body Waves[J]. BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA,2023,113(5).

Jiang, Yan,&Chen, Xiaofei.(2023).Finite-Frequency Delay Times of Phase Segments for Body Waves.BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA,113(5).

Jiang, Yan,et al."Finite-Frequency Delay Times of Phase Segments for Body Waves".BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA 113.5(2023).