FK results expressed in propagation azimuth or backazimuth?

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admin
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FK results expressed in propagation azimuth or backazimuth?

Post by admin »

> Hi Marc,
>
> just two very short questions, I can't remember...
>
> 1) the slowness /wavenumber vector definition in geopsy points
> in direction of propagating wave (correct definition) or points
> towards the source (convenient definition, but opposite direction)?
> 2) backazimuth is measured N over E and math-pi is
> measured E over N, correct?
>
> thanks for your response
> bye
> Matthias

admin
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Posts: 433
Joined: Mon Aug 13, 2007 11:48 am
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Post by admin »

This question is always asked and I'm never completely sure... I would say that everything is expressed in propagating azimuth. To ensure it I built a small synthetic database where I'm sure of the direction and the propagation slowness.

Here is a description of the synthetic case:
Image
6 stations, R001 and R002 are in phase, R003 is delayed by 0.866 seconds, R004 and R005 by 0.433 seconds, R006 is slightly in advance. Hence it is a monochromatic wave at 1 Hz traveling in direction 120
Attachments
azimuth_fk_tester.png
Array geometry, signals and FK map
(40.8 KiB) Downloaded 495 times
azimuth_fk_tester.tar.gz
Synthetic tester
(259.97 KiB) Downloaded 904 times

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