Privacy Policy Disclaimer
  Advanced SearchBrowse




Journal Article

Fast and Robust Earthquake Source Spectra and Moment Magnitudes from Envelope Inversion


Eulenfeld,  Tom
External Organizations;


Dahm,  T.
2.1 Physics of Earthquakes and Volcanoes, 2.0 Geophysics, Departments, GFZ Publication Database, Deutsches GeoForschungsZentrum;

Heimann,  Sebastian
External Organizations;

Wegler,  Ulrich
External Organizations;

External Ressource
No external resources are shared
Fulltext (public)

(Postprint), 4MB

Supplementary Material (public)
There is no public supplementary material available

Eulenfeld, T., Dahm, T., Heimann, S., Wegler, U. (2022): Fast and Robust Earthquake Source Spectra and Moment Magnitudes from Envelope Inversion. - Bulletin of the Seismological Society of America, 112, 2, 878-893.

Cite as: https://gfzpublic.gfz-potsdam.de/pubman/item/item_5008835
With the present study, we introduce a fast and robust method to calculate the source displacement spectra of small earthquakes on a local to regional scale. The work is based on the publicly available Qopen method of full envelope inversion, which is further tuned for the given purpose. Important source parameters—seismic moment, moment magnitude, corner frequency, and high‐frequency fall off—are determined from the source spectra by fitting a simple earthquake source model. The method is demonstrated by means of a data set comprising the 2018 West Bohemia earthquake swarm. We report moment magnitudes, corner frequencies, and centroid moment tensors inverted from short‐period body waves with the Grond package for all earthquakes with a local magnitude larger than 1.8. Moment magnitudes calculated by envelope inversion show a very good agreement to moment magnitudes resulting from the probabilisitc moment tensor inversion. Furthermore, source displacement spectra from envelope inversion show a good agreement with spectra obtained by multiple taper analysis of the direct onsets of body waves but are not affected by the large scatter of the second. The seismic moments obtained with the envelope inversion scale with corner frequencies according to M0∝f−4.7c⁠. Earthquakes of the present data set result in a smaller stress drop for smaller magnitudes. Self‐similarity of earthquake rupture is not observed. In addition, we report frequency‐dependent site amplification at the used stations.