Moment tensor inversion of waveforms: a two-step time-frequency approach

Vavryčuk, Václav; Kühn, Daniela

doi:10.1111/j.1365-246x.2012.05592.x

Cited by 65 publications

(39 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Several procedures have been proposed to estimate the focal mechanism of low-magnitude earthquakes by using high-frequency seismograms recorded at local stations (e.g. Šílený et al 1992;Mao et al 1994;Panza & Sarao 2000;Sarao et al 2001;Vavryčuk & Kühn 2012).…”

mentioning

confidence: 99%

Probabilistic waveform inversion for 22 earthquake moment tensors in Hungary: new constraints on the tectonic stress pattern inside the Pannonian basin

Wéber¹

2015

Geophysical Journal International

View full text Add to dashboard Cite

S U M M A R YWe have successfully estimated the full moment tensors of 22 local earthquakes with local magnitude ranging from 1.2 to 4.8 that occurred in the Hungarian part of the Pannonian basin between 1995 and 2014. We used a probabilistic waveform inversion procedure that takes into account the effects of the random noise contained in the seismograms, the uncertainty of the hypocentre determined from arrival times and the inaccurate knowledge of the velocity structure, while estimating the error affecting the derived focal parameters. The applied probabilistic approach maps the posterior probability density functions (PPDFs) for both the hypocentral coordinates and the moment tensor components. The final estimates are given by the maximum likelihood points of the PPDFs, while solution uncertainties are presented by histogram plots. The estimated uncertainties in the moment tensor components are plotted on the focal sphere in such a way, that the significance of the double couple (DC), the compensated linear vector dipole (CLVD) and the isotropic (ISO) parts of the source can be assessed. We have shown that the applied waveform inversion method is equally suitable to recover the source mechanism for low-magnitude events using short-period local waveforms as well as for moderate-size earthquakes using long-period seismograms. The non-DC components of the retrieved focal mechanisms are statistically insignificant for all the analysed earthquakes. The negligible amount of the ISO component implies the tectonic nature of the investigated events. The moment tensor solutions reported by other agencies for five of the M L > 4 earthquakes studied in this paper are very similar to those calculated by the applied waveform inversion algorithm. We have found only strike-slip and thrust faulting events, giving further support to the hypothesis that the Pannonian basin is currently experiencing a compressional regime of deformation. The orientations of the obtained focal mechanisms are in good agreement with the main stress pattern published for the Pannonian region. The azimuth of the subhorizontal P principal axis varies from about NNE-SSW in SW Hungary through NE-SW well inside the basin to around E-W in the NE part of the country. Most of the analysed earthquakes occurred on faults or subfaults differently oriented than the main fault system.

show abstract

mentioning

confidence: 99%

Probabilistic waveform inversion for 22 earthquake moment tensors in Hungary: new constraints on the tectonic stress pattern inside the Pannonian basin

Wéber¹

2015

Geophysical Journal International

View full text Add to dashboard Cite

show abstract

“…Over the last decades, several studies focused on source mechanisms of mining events, using different inversion approaches (e.g., Gibowicz, 1990;McGarr, 1992a,b;Fletcher and McGarr, 2005;Dreger et al, 2008;Lizurek and Wiejacz, 2011;Vavryčuk and Kühn, 2012;Sen et al, 2013). As for tectonic events, some mining-induced earthquake sources can be well modeled by a double-couple (DC) source model (e.g., Dahm et al, 1999;Richardson et al, 2005).…”

Section: Introductionmentioning

confidence: 99%

Complex Rupture Process of the 19 March 2013, Rudna Mine (Poland) Induced Seismic Event and Collapse in the Light of Local and Regional Moment Tensor Inversion

Rudziński¹,

Cesca²,

Lizurek³

2016

Seismological Research Letters

View full text Add to dashboard Cite

On 19 March 2013, a strong, shallow, induced seismic event struck a mining panel in the room-and-pillar Rudna copper mine in southeastern Poland. The event caused important damage at the mining tunnel and trapped 19 miners, who were safely rescued a few hours later. Although mining-induced seismicity is frequent at this mine, the 19 March event was unusual because of its larger magnitude, its occurrence far from the mining stopes, and because it was accompanied by a strong hazardous rockburst. The mining inspections following the event verified the occurrence of a rockfall with tunnel floor uplift but also recognized the presence of a faulting structure at the hypocentral location. The availability of three monitoring networks (including local and regional data, short-period and broadband seismometers, and surface and in-mine installation) presented an optimal setup to determine rupture parameters and to compare the performance and results from different installations. We performed waveform and spectral-based analysis to infer source properties, with a particular interest to the determination of the rupture processes, using different moment tensor (MT) inversion techniques. Our results are surprisingly different, ranging from a dominant thrust mechanism, resolved at closest distances, to a collapse-type rupture, resolved at regional distances. We demonstrate that a complex rupture model is needed to explain all observations and to justify these discrepancies. The final scenario indicates that the rupture nucleated as a weaker thrust mechanism along a pre-existing weakened surface and then continued in a more energetic collapse event. The local LUMINEOS surface network has the potential to resolve both subevents but not using a standard MT decomposition. Here, we propose a new MT decomposition and an alternative MT fitting procedure that can be used to analyze the MT of collapse sources.Online Material: Tables of regional stations and source parameters, and figure of displacement seismograms.

show abstract

“…The analysis of the STF is typically performed for larger earthquakes, where its analysis can be used e.g., to identify double or multiple events. A second type of applications concerns the analysis of microseismicity, e.g., in mines ( Sílený, P sen cík, & Young, 2001;Teyssoneyre, Feignier, Sílený, & Coutant, 2002;Vavry cuk & K€ uhn, 2012), or volcano seismicity (e.g., Auger, D'Auria, Martini, Chouet, & Dawson, 2006;Cesca, Braun, Tessmer, & Dahm, 2007;Ohminato, Chouet, Dawson, & Kedar, 1998). Even in this case, it is typically assumed that a single time history is common to most (or all) moment tensor components, so that the source can be described by a single normalized moment tensor and a few (or one) source time functions.…”

Section: The Microseismic Sourcementioning

confidence: 99%