[obspy-users] Characteristics on Bode plot using Inventory.plot_response

Sigward Funke sfunke at uni-leipzig.de
Fri Nov 10 10:45:04 CET 2017


Hi Tobias,

thanks for fast and clear explanation. So not corner frequency is annotated 
but frequency of overall sensitivity - makes sense.

Best Regards
Sigward

On Freitag, 10. November 2017 10:35:55 CET Tobias Megies wrote:
> Hi Sigward,
> 
> the values you see as annotations to the amplitude spectrum in the Bode
> plot are simply what is specified for the overall sensitivity in the
> given station metadata:
> 
> from obspy import read_inventory
> response = read_inventory()[0][0][0].response
> print(response)
> print(response.instrument_sensitivity)
> 
> Instrument Sensitivity:
> 	Value: 943680000.0
> 	Frequency: 0.02
> 	Input units: M/S
> 	Input units description: Velocity in Meters per Second
> 	Output units: COUNTS
> 	Output units description: Digital Counts
>  
> Usually this should be within the flat part of the response.
> 
> best,
> Tobias
> 
> On 10/11/17 10:10, Sigward Funke wrote:
> > Dear people of ObsPy,
> > 
> > where can I find some details (documentation) about 2 highlighted numbers
> > on Bode plot using Inventory.plot_response (see [1])?
> > 
> > * Right value shows plateau of amplitudes -- it's clear for me;
> > in [1]: 9.4e+08.
> > * But top value (in [1]: 0.02Hz = 50s) often don't show expected flat
> > regions lower corner frequency. Without knowledge of es
> > rdxample's details I
> > would expect in case [1] something around 0.01Hz = 100s (probably 120s =
> > STS2?). At least one of my STS2-plots shows exactly the same unexpected
> > value.
> > 
> > In my examples in 6 of 7 cases highlighted frequency don't match lower
> > corner, but in one case it fits well. So it could be possible that I'm
> > wrong to expect lower corner frequency for highlighting - but what else
> > frequency could be highlighted otherwise?
> > 
> > Best Regards
> > Sigward
> > 
> > [1] https://docs.obspy.org/packages/autogen/
> > obspy.core.inventory.response.Response.plot.html
> > 
> > 
> > 
> > _______________________________________________
> > obspy-users mailing list
> > obspy-users at lists.swapbytes.de
> > http://lists.swapbytes.de/mailman/listinfo/obspy-users


-- 
Sigward Funke          Institut für Geophysik und Geologie
Tel. 0341 97-32816                     Universität Leipzig
Fax. 0341 97-32809               Talstr. 35, 04103 Leipzig
E-mail: sfunke at uni-leipzig.de                    Raum 2-15



More information about the obspy-users mailing list