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Dear Marc,

I have a question on the use of gpviemax or gphistogram of the new release 3.4.1, after a RTBF analysis performed on 3C passive data.

gpviemax produces always a result as in attach; I mean using no option, or using the option -R the output does not change (this is what I argue). The output in this example is with two well defined modes (I suppose Rayleigh) and the plot is distributed in 3 columns: the first column the two modes are together, and 2nd and 3rd the modes are separated. I cannot find more the option -L in gpviemax.


For gphistogram my comment is the same; it displays the results with the two modes but the option -L (and -R) seems no more present, or are probably with a different sintax

So if I am correct, my main question is:
How can I separate R and L contributions from the *max file after a RTBF 3c component using gpviemax or gphistogram?

Many thanks and my best
Giuseppe

Hi Giuseppe,

Effectively it is no longer possible to separate Love and Rayleigh in .max because the current .max files do not contain both types of waves as it was the case in previous releases (<=3.3.x). The simultaneous computation of Love and Rayleigh was not saving much time and some parameters, optimum for Rayleigh, are not for Love. For instance, the number of blocks in the block average must be greater for Rayleigh than for Love.

In the plot you sent, you have only Rayleigh. Note that gpviewmax splits positive and negative ellipticities, and currently for testing, an automatic picking.

To get the Love dispersion curve, you have to re-run geopsy-fk 'LDS' process type (Love Direct Steering) is not yet debugged (under intensive development for next branch 3.5). Inside the graphical interface, 'CaponTransverse' is not yet available. It will be available for 3.4.2

Regards,

Marc

Hi Marc
it means that to obtain R and L waves I have to run geopsy-fk two times,
firstly with the RTBF option in order to obtain the R dispersion curve
and then with the CaponTransverse option to obtain only the Love waves.

In the second case, I attach the Love curves obtained consistently with the previous message: of course there is no more ellipticipty information in the max file which you set per default to nan

Further the automatic picking seems me (limited to this example) works fine
Thanks to your support and patience now clear

Giuseppe

I will put the ellipticity of Love wave to 'inf' for the next release. It is also set to 'nan' if you run a classical vertical FK.

Hi Marc,
is the procedure you described also applicable for Windows?
I remember playing with tutorial data (lep ring01 3c) and with a version of Geopsy 3.2 and getting Rayleigh and Love with a single run (as per documentation). It's correct?

Regards

Luigi

Yes, it applies to both Windows and Linux (and Mac). On branch 3.3, Rayleigh and Love were computed in a single run but with the disadvantages listed above.