DYNAMICS and ACTIVE PROCESSES - International Lithosphere ...

Fig. 2: Epicentral map of September 6, 2009 (21:49 UTC) main shock and its imediately subsequent
aftershocks in connection with the distribution of BB seismological stations and focal mechanism
solution of Gjorica earthquake.
Spectral analyze has been performed based on the Brune (1970) theoritical model for source
displacement spectrum, taking into acount various assumption on geometrical spreading factor and
anelastic attenuation due to local heterogenity effect on traveling seismic wave energy (Fig. 3).
Fig. 3: Displacement Spectras from horizontal components, for the September 6, 2009 event (21:49
UTC).
Seismic energy, radiated from September 6, 2009 event source express a significant macroscopic
parameter to evaluate the seismic potential witch lead to the macroseismic effect in a broad area. To
determine this parameter, dynamic methode has been used. This methode takes into acount the
velocity power spectra integrated over frequency. These corrected velocity spectra for each of the
horizontal component have been determined (Fig. 5), from velocity seismic traces corrected for the
effect of recording instrument response, (Fig. 4).
Velocity
0.0001
0.0000
-0 .0 0 0 1
0.0 0.5 1.0 1.5 2.0 2.5 3.0
0.0001
Z
0.0000
-0 .0 0 0 1
0.0 0.5 1.0 1.5 2.0 2.5 3.0
0.0001
N
0.0000
-0 .0 0 0 1
m /s
0.0 0.5 1.0 1.5 2.0 2.5 3.0
Time m in
�
Fig. 4: Three velocity trace waveforms, corrected for instrument response, of BCI records of
September 6, 2009 event (21:49 UTC).
52
E