[MSNoise] MSNoise Digest, Vol 31, Issue 1

[Esteban Chaves]

Hi Ashton, 

As an active user:

I highly recommend you to check the documentation: http://msnoise.org/doc/workflow.html#module-msnoise.s03compute_cc <http://msnoise.org/doc/workflow.html#module-msnoise.s03compute_cc>
I think the pre-processing and processing steps are well documented in the web site. 

1) Yes. It is more efficient to compute the cross-correlation functions or Green’s functions using 30-min chunks. Although you can change this feature if you will. Segments are re-build afterwards. 

2) You need to define the filters in order to compute the cross-correlations and extract the coherent part of the ambient noise for a given frequency range. MWCS is used to compute the moving window cross spectral analysis after the cross-correlation procedure. 

3) dunno. May be Thomas can give you more info. 

-Esteban J. Chaves


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> Today's Topics:
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>   1. new user (Flinders, Ashton)
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> ----------------------------------------------------------------------
> 
> Message: 1
> Date: Wed, 5 Oct 2016 13:10:53 -0700
> From: "Flinders, Ashton" <aflinders at usgs.gov>
> To: <msnoise at mailman-as.oma.be>
> Subject: [MSNoise] new user
> Message-ID:
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> 
> Hi all, long-time obspy user new MSnoise user.
> 
> I just had a couple quick questions I was hoping to get clarification on;
> 
>> From the SRL article;
> "Once all waveforms are loaded in memory, the computation is done by
> iteration of the station pairs, on the different components to compute and
> the on the different filters for each defined window (30 minutes slices by
> default)."
> 
> 1) To be clear, the two time-series from a station-station pair are divided
> into segments (30 minutes long, no overlap, by default), and the CC is done
> on these segments? Are these segments then rebuilt into the daily CCF? Is
> this segmentation purely for efficieny reasons, or is there something else
> going on?
> 
> 2) Why does msnoise compute_cc, not work if there is no MCWS filter defined?
> 
> 3) Is there an intelligent way to search the mailing list archive?
> 
> Thanks for the help!
> 
> -ashton
> 
> 
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> End of MSNoise Digest, Vol 31, Issue 1
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