Moment Magnitude MW

Last Update by Orefice A. on May 23, 2012

MW: 6.1 ± 0.3  
fc(Hz): 0.15 ± 0.09

Plot of all S-wave displacement spectra before (top) and after (bottom) the correction for the attenuation parameters t*. By iterative procedure we obtained a mean values of t* equal to (0.09 +/- 0.04)s. The red curve is the best fit spectrum computed with moment magnitude, corner frequency and t* values estimated for the event.



Spectra Displacement for single station

Examples of fit between observed and calculated displacement spectra. We adopted an iterative, multi-step approach for the inversion of S-displacement spectra assuming a omega-gamma source model (Stabile et al, 2012). We applied the non-linear Levenberg-Marquardt least-square algorithm (Marquardt,1963), implemented in the software package GNUPLOT (Janert , 2009), for curve fitting and parameters estimation.
The S-wave modulus displacement spectrum is obtained from the spectra of the two horizontal accelerometric components and it is inverted in the frequency range [0.02-5] Hz.