Near Surface Geophysics > VSP and depth conversion

For near surface vertical seismic profile, slim hole VSP tools and light seismic sources are usually used. The slim hole VSP tool is either a single component tool or a multi component tool.

The example describes the different processing steps of a near surface VSP recorded on the Experimental Site of Vesdun. It shows how filter based on Singular Value Decomposition can be used to separate the different wave fields, when the number of traces which composed the near surface VSP is limited (13).

The example shows the procedure used to convert in depth seismic sections processed in time.

Figure shows step by step:

  • Step 1: the VSP tool designed to record the wave fields on 3 components: a vertical geophone Z and 2 horizontal orthogonal geophones H1 and H2.The tool has two arms used to optimize its coupling with the geological formation.

  • Step 2: the seismic source. It is a light weight dropper.