Source time functions
The DMC is now calculating source-time functions (STFs) for M7.0+ earthquakes at GSN and other stations automatically (without human review). The STFs are calculated using point-source synthetic seismograms (theoretical Green’s functions) along with vertical component (LHZ channel) recordings of short-arc Rayleigh waves (R1). STFs are estimated using a simple two-source forward modeling approach by sweeping through the parameter space of two smoothed triangle and/or trapezoid functions of various widths, offset and amplitude and retaining the best fitting solution.
Results in SPUD:
by Alex Hutko (IRIS Data Management Center) and Chad Trabant (IRIS DMC)