The hydrophone VSP has been recorded at well M20 on the Hydrogeological Experimental Site of the University of Poitiers. The example shows how wavenumber filter and velocity filter in the f, k domain can be combined to separate the different wave fields. It also shows how the Hilbert transform and the analytic signal can be used to analyze the amplitude of the different waves.

The field example and the next one entitled " Acoustic logging at well M20" are also used to show the contribution of VSP and full waveform acoustic data to reservoir characterization, detection of water productive layers and flows.

Figure shows step by step :

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  Step 1: the site and the location of the well M20.


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  Step 2: the VSP tool. It is a borehole hydrophone.


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  Step 3: the seismic source. It is a light weight dropper.