Seismic prompt gravity strain signals in a layered spherical Earth

Zhang, Shenjian1; Wang, Rongjiang2; Chen, Xiaofei1,3,4

2023-10-01

10.1016/j.eqs.2023.09.002

EARTHQUAKE SCIENCE   Impact Factor & Quartile

1674-4519

1867-8777

Seismic waves generated by an earthquake can produce dynamic perturbations in the Earth's gravity field before the direct arrival of P-waves. Observations of these so-called prompt elasto-gravity signals by ground-based gravimeters and broadband seismometers have been reported for some large events, such as the 2011 MW9.1 Tohoku earthquake. Recent studies have introduced prompt gravity strain signals (PGSSs) as a new type of observable seismic gravity perturbation that can be used to measure the spatial gradient of the perturbed gravity field. Theoretically, these types of signals can be recorded by indevelopment instruments termed gravity strainmeters, although no successful detection has been reported as yet. Herein, we propose an efficient approach for PGSSs based on a multilayered spherical Earth model. We compared the simulated waveforms with analytical solutions obtained from a homogeneous half-space model, which has been used in earlier studies. This comparison indicates that the effect of the Earth's structural stratification is significant. With the help of the new simulation approach, we also demonstrated how the PGSSs depend on the magnitude of the seismic source. We further conducted synthetic tests estimating earthquake magnitude using gravity strain signals to demonstrate the potential application of this type of signal in earthquake early warning systems. These results provide essential information for future studies on the synthesis and application of earthquake-induced gravity strain signals.

gravity strain synthetic seismogram earthquake early warning system

ESCI

English

First ; Corresponding

National Natural Science Foundation of China["U1901602","42204060"] ; Guangdong Provincial Key Laboratory of Geophysical High -Resolution Imaging Technology[2022B1212010002] ; Shenzhen Key Laboratory of Deep Offshore Oil and Gas Exploration Technology[ZDSYS20190902093007855]

Geochemistry & Geophysics

Geochemistry & Geophysics

WOS:001090259000001

KEAI PUBLISHING LTD

Web of Science

1.Southern Univ Sci & Technol, Dept Earth & Space Sci, Shenzhen 518055, Peoples R China
2.GFZ German Res Ctr Geosci, Helmholtz Ctr Potsdam, D-14473 Potsdam, Germany
3.Southern Univ Sci & Technol, Guangdong Prov Key Lab Geophys High Resolut Imagin, Shenzhen 518055, Peoples R China
4.Southern Univ Sci & Technol, Shenzhen Key Lab Deep Offshore Oil & Gas Explorat, Shenzhen 518055, Peoples R China

Zhang, Shenjian,Wang, Rongjiang,Chen, Xiaofei. Seismic prompt gravity strain signals in a layered spherical Earth[J]. EARTHQUAKE SCIENCE,2023,36(5).

Zhang, Shenjian,Wang, Rongjiang,&Chen, Xiaofei.(2023).Seismic prompt gravity strain signals in a layered spherical Earth.EARTHQUAKE SCIENCE,36(5).

Zhang, Shenjian,et al."Seismic prompt gravity strain signals in a layered spherical Earth".EARTHQUAKE SCIENCE 36.5(2023).