Ambient vibration array

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Common pre-requisites for array processing - getting ready

Loading signals

View time series

Group signals

Insert / edit station coordinates

F-K Toolbox (conventional f-k)

Signal viewer for one group of simultaneously recorded waveforms ready for array processing

If you have followed all steps above you should have now a set of simultaneously recorded waveforms building a group and containing coordinates for each waveform. You can view this group of waveforms in the data viewer and should get a picture like the one shown to the right.

Now you can open the conventional frequency wavenumber toolbox by pushing the plugin icon FKToolboxPluginIcon.png.

The f-k toolbox should open and is now attached to the signal viewer. No other toolbox will now open with the signals you have loaded to the signal viewer. In order to process the same data set by another tool, you have to open them in a different signal viewer window. Note also, that once you close either the f-k toolbox window or the signal viewer, there is no way to undo this action - you will have to start again by opening a new signal viewer and attaching the f-k toolbox to it. Alternatively you can drag your group directly into the f-k toolbox icon. Geopsy will automatically open a new exclusively attached signal viewer for you.

Saving results / contents of output file

Graphical display of f-k results using max2curve

max2curve

High resolution frequency wavenumber Toolbox (Capon's method)

Saving results / contents of output file

Graphical display of f-k results using max2curve

Modified Spatial Autocorrelation (MSPAC) Toolbox

The Modified Spatial Autocorrelation (MSPAC) was introduced by [1] following Aki (1957). This method allows computing spatial autocorrelation coefficients for any arbitary array layouts.


Saving results / contents of output file

Graphical display of f-k results using max2curve

spac2disp

References

  1. Bettig B., P.-Y. Bard, F. Sherbaum, J. Riepl, F. Cotton, C. Cornou, D. Hatzfeld, 2001. Analysis of dense array measurements using the modified spatial auto-correlation method (SPAC). Application to Grenoble area., Boletin de Geofisica Teoria e Applicata, 42, 3-4, 281-304.

Further readings