Seismic source tracking with six degree-of-freedom ground motion observations
Type
ArticleAuthors
Yuan, Shihao
Gessele, Kilian
Gabriel, Alice-Agnes

May, Dave A.
Wassermann, Joachim

Igel, Heiner
KAUST Grant Number
ORS-2017-CRG6 3389.02Date
2021-03-10Online Publication Date
2021-03-10Print Publication Date
2021-03Embargo End Date
2021-08-04Submitted Date
2020-10-06Permanent link to this record
http://hdl.handle.net/10754/667329
Metadata
Show full item recordAbstract
Back azimuth information can be determined from combined measurements of rotations and translations at a single site. Such six degree-of-freedom (6-DoF) measurements are reasonably stable in delivering similar information compared to a small-scale array of three-component seismometers. Here we investigate whether a 6-DoF approach is applicable to tracking seismic sources. While common approaches determining the timing and location of energy sources generating seismic waves rely on the information of P-waves, here we use S-waves. We track back azimuths of directly arriving SH-waves in the 2-D case, P-converted SV-waves, direct SV- and direct SH-waves in the 3-D case. For data analysis, we compare a cross-correlation approach using a grid-search optimization algorithm with a polarization analysis method. We successfully recover the rupture path and rupture velocity with only one station, under the assumption of an approximately known fault location. Using more than one station, rupture imaging in space and time is possible without a priori assumptions. We discuss the effects of rupture directivity, supershear rupture velocity, source-receiver geometry, wavefield interference, and noise. We verify our approach with the analysis of moving traffic noise sources using 6-DoF observations. The collocated classic seismometer and newly-built ring laser gyroscope ROMY near Munich, Germany, allow us to record high-fidelity, broadband 6-DoF (particle velocity and rotational rate) ground motions. We successfully track vehicles and estimate their speed while traveling along a nearby highway using the estimated BAz as a function of time of a single station observation.Citation
Yuan, S., Gessele, K., Gabriel, A., May, D. A., Wassermann, J., & Igel, H. (2021). Seismic source tracking with six degree-of-freedom ground motion observations. Journal of Geophysical Research: Solid Earth. doi:10.1029/2020jb021112Sponsors
European Research Council. Grant Number: 339991 European Research Council. Grant Number: 852992 H2020 European Research Council. Grant Number: 823844 Deutsche Forschungsgemeinschaft (DFG). Grant Number: GA 2465/2-1,GA 2465/3-1 KAUST | Global Collaborative Research, King Abdullah University of Science and Technology (GCR, KAUST). Grant Number: ORS-2017-CRG6 3389.02Publisher
American Geophysical Union (AGU)Additional Links
https://onlinelibrary.wiley.com/doi/10.1029/2020JB021112ae974a485f413a2113503eed53cd6c53
10.1029/2020jb021112