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[claudiodsf]

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[anniejerk]

Hi,
I’d like to try using a different velocity model instead of iasp91 to compute the takeoff angles when incorporating the radiation pattern and focal mechanism in the analysis. Is this currently possible?

[claudiodsf]

Hi @anniejerk. I don't have enough clues to help you. Could you try sharing somewhere a complete working example, with input files and your configuration?

[anniejerk]

sourcespec (3).zip

[claudiodsf]

Thanks,

I could run your test and found two problems:

1. A bug in SouceSpec preventing the grids to being correctly read. This is fixed in the latest development version, which you can install through pip install git+https://github.com/SeismicSource/sourcespec.git

2. Your grids are not correctly constructed: the epicenter is on the (0, 0) position, which is the lower-left corner of the grid. Since your model is 1D, you could construct a simpler 2D grid with something like VGGRID 2 250 10 0.0 0.0 -5.0 10.0 10.0 10.0 SLOW_LEN (note the first value of "2" for the number of x points). You should then use GTMODE GRID2D ANGLES_YES

[anniejerk]

Thank you so much!

[anniejerk]

Hopefully last question! and thank you so much for the help so far. I downloaded the new package and made a 2D grid. I currently have my picks in a .xml file. Do I have to compute relative times for each sensor to get it work, or will Sourcspec use my arrivals from the .xml for the computation? I get very large residuals, when I know in fact that this model should in theory should give a better estimate for my theoretical picks.
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ource depth: 15 km, vp_source: 6.2 km/s, vs_source: 3.58 km/s, rho_source: 2720 kg/m3
Processing traces...
NS.BER.00.HHE: measured P pick time - theoretical time = -70.3 s, above tolerance of 8.0 s
NS.BER.00.HHE: no P pick found
NS.BER.00.HHE: using theoretical P pick from NonLinLoc grid
NS.BER.00.HHE: measured S pick time - theoretical time = -120.9 s, above tolerance of 8.0 s
NS.BER.00.HHE: no S pick found

NS.BER.00.HHE: using theoretical S pick from NonLinLoc grid
NS.BER.00.HHE broadb: clipping score: 0.0%
NS.BER.00.HHE broadb: S/N: 0.1
NS.BER.00.HHE broadb: S/N smaller than 1: skipping trace
NS.BER.00.HHN: measured P pick time - theoretical time = -70.3 s, above tolerance of 8.0 s
NS.BER.00.HHN: no P pick found
NS.BER.00.HHN: using theoretical P pick from NonLinLoc grid
NS.BER.00.HHN: measured S pick time - theoretical time = -120.9 s, above tolerance of 8.0 s
NS.BER.00.HHN: no S pick found
NS.BER.00.HHN: using theoretical S pick from NonLinLoc grid
NS.BER.00.HHN broadb: clipping score: 0.0%
NS.BER.00.HHN broadb: S/N: 0.1

NS.BER.00.HHN broadb: S/N smaller than 1: skipping trace

Here are my current nonlinloc files :)
2D_grid.zip