scholarly journals Moment magnitude estimates for Central Anatolian earthquakes using coda waves

2019 ◽  
Author(s):  
Tuna Eken
Keyword(s):  
Empirical Relation ◽  
Active Regions ◽  
Moment Magnitude ◽  
Central Anatolia ◽  
Coda Wave ◽  
Seismic Experiment ◽  
Tectonically Active ◽  
Passive Seismic ◽  
Passive Seismic Experiment ◽  
Good Agreement

Abstract. Proper estimate of moment magnitude that is a physical measure of the energy released at earthquake source is essential for better seismic hazard assessments in tectonically active regions. Here a coda wave modeling approach that enables the source displacement spectrum modeling of examined event was used to estimate moment magnitude of central Anatolia earthquakes. To achieve this aim, three component waveforms of local earthquakes with magnitudes 2.0 ≤ ML ≤ 5.2 recorded at 72 seismic stations which have been operated between 2013 and 2015 within the framework of the CD-CAT passive seismic experiment. An inversion on the coda wave traces of each selected single event in our database was performed in five different frequency bands between 0.75 and 12 Hz. Our resultant moment magnitudes (MW-coda) exhibit a good agreement with routinely reported local magnitude (ML) estimates for study area. Finally, we present an empirical relation between MW-coda and ML for central Anatolian earthquakes.

scholarly journals Moment magnitude estimates for central Anatolian earthquakes using coda waves

Solid Earth ◽  
2019 ◽  
Vol 10 (3) ◽  
pp. 713-723 ◽  
Author(s):  
Tuna Eken
Keyword(s):  
Empirical Relation ◽  
Active Regions ◽  
Sampling Interval ◽  
Moment Magnitude ◽  
Central Anatolia ◽  
Coda Wave ◽  
Anelastic Attenuation ◽  
Seismic Experiment ◽  
Tectonically Active ◽  
Passive Seismic

Abstract. A proper estimate of moment magnitude, which is a physical measure of the energy released at an earthquake source, is essential for better seismic hazard assessments in tectonically active regions. Here a coda wave modeling approach that enables the source displacement spectrum modeling of the examined event was used to estimate moment magnitudes of central Anatolia earthquakes. To achieve this aim, three-component waveforms of local earthquakes with magnitudes 2.0≤ML≤5.2 recorded at 69 seismic stations, which were operated between 2013 and 2015 within the framework of the Continental Dynamics–Central Anatolian Tectonics (CD–CAT) passive seismic experiment, were utilized. An inversion on the coda wave traces of each selected single event in the database was performed in five different frequency bands between 0.75 and 12 Hz. The resultant moment magnitudes (Mw coda) exhibit a good agreement with routinely reported local magnitude (ML) estimates for the study area. Apparent move-out that is particularly significant around the scattered variation of ML–Mw coda data points for small earthquakes (ML < 3.5) can be explained by possible biases of wrong assumptions to account for anelastic attenuation and seismic recordings with a finite sampling interval. Finally, I present an empirical relation between Mw coda and ML for central Anatolian earthquakes.

Coda-derived moment magnitudes in central Anatolia

2020 ◽  
Author(s):  
Tuna Eken
Keyword(s):  
Volume Averaging ◽  
Sampling Interval ◽  
Seismic Attenuation ◽  
Coda Waves ◽  
Central Anatolia ◽  
Theory Approach ◽  
Anelastic Attenuation ◽  
Seismic Experiment ◽  
Tectonically Active ◽  
Passive Seismic

&lt;p&gt;A reliable representation of the energy at the earthquake source is vitally important to make reliable seismic hazard assessments in tectonically active areas. The use of coda waves, for this aim, can provide source spectra for robust moment magnitude estimates mainly due to its volume-averaging property sampling the entire focal sphere as this makes these waves insensitive to any source radiation pattern effect. In the present study, we examined local earthquakes beneath central Anatolia earthquakes with magnitudes 2.0&amp;#8804;ML&amp;#8804;5.2 recorded at 69 seismic stations that were operated between 2013 and 2015 within the framework of the Continental Dynamics&amp;#8211;Central Anatolian Tectonics (CD&amp;#8211;CAT) passive seismic experiment. The inversion scheme used here involved simultaneous modeling of source properties as well as seismic attenuation parameters in five different frequency bands between 0.75 and 12&amp;#8201;Hz. Forward modeling of coda waves was achieved through an isotropic acoustic Radiative Transfer Theory approach. A comparison between coda derived (M&lt;sub&gt;w&lt;/sub&gt; coda) and routinely reported local (M&lt;sub&gt;L&lt;/sub&gt;) magnitudes shows an overall consistency. However, apparent move-out observed around small earthquakes (M&lt;sub&gt;L&lt;/sub&gt;&amp;#8201;&lt;&amp;#8201;3.5) can be attributed to wrong assumptions for anelastic attenuation as well as to the use of seismic recordings with a finite sampling interval.&lt;/p&gt;

scholarly journals Passive seismic experiment and ScS wave splitting in the southwestern subbasin of South China Sea

2012 ◽  
Vol 57 (25) ◽  
pp. 3381-3390 ◽  
Author(s):  
AiGuo Ruan ◽  
JiaBiao Li ◽  
ChaoShing Lee ◽  
XueLin Qiu ◽  
ShaoJun Pan
Keyword(s):  
South China Sea ◽  
South China ◽  
China Sea ◽  
Seismic Experiment ◽  
Wave Splitting ◽  
Passive Seismic ◽  
Passive Seismic Experiment
Sign in / Sign up

Export Citation Format

Share Document