Borehole seismic surveying: 3C-3D VSP and land vertical cable analysis

Jitendra S. Gulati

This thesis presents analysis of data from two new borehole seismic methods, namely the 3C-3D vertical seismic profile (VSP) and the land vertical cable techniques. Synthetic seismograms and field data from surveys over the Blackfoot oil field in Alberta, Canada are used for the analysis.

Processing flows for the two techniques are developed. A method that uses statistical velocity analysis for VSPCDP stacking is also implemented.

Hodogram analysis, median filtering, VSPCDP stack, and f-xy deconvolution are key steps used in processing the 3C-3D VSP data. Processing of the land vertical cable data primarily involved predictive deconvolution, velocity filtering, VSPCDP stacking, and migration.

The structural images from the two techniques are correlated and interpreted with previously interpreted surface seismic images. Evidence of the productive region (a Glauconitic sand channel) on the 3-D VSP time slices and on the land vertical cable image indicate the promise of these techniques.