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Paul Ogwari University of Memphis Center for Earthquake Research and Information 2 nd year MSc. Research on: Effects of Type of Faulting on Earthquake Ground Motions in NMSZ.
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Paul OgwariUniversity of MemphisCenter for Earthquake Research and Information2nd year MSc Research on: Effects of Type of Faulting on Earthquake Ground Motions in NMSZ • Evaluate the effect of type of faulting on earthquake ground motion (horizontal) by defining the distance scaling for earthquakes in the New Madrid Seismic Zone. • Multistage processing of seismic network data utilizing a coda normalization technique proposed by Aki (1980)
PASSCAL PQL (identify clean traces) Remove Instrument Response Rotate the seismogram Data processing Fortran (running memory consuming loops) Filter the seismogram: (1;2;3;4;5;6;8;10;12;14;16) Integrate the square velocity and choose time window corresponding to 5-75% of energy from the onset of the S wave arrival Condition: qualify only frequencies where the signal to noise ratio is >4 Matlab (run most of the process) Choose a CODA window equal to signal window at >2 Get the absolute maximum amplitude of the filtered time series Get the rms of CODA from the filtered time series Get the rms of FFT of the Original time series for signal window chosen above: the freq window is Freq: Stn Name: Peak_Vel_Amp: RMS_FFT_Amp: CODA_Amp(s): Distance: S_time: Coda_Env: Sign_duration: Future Pick phases and make some sense out of traces • Regression of coda normalized amplitude for attenuation relationships • And • Regression of peak amplitude for Source and site function