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The vertical seismic profile (VSP) is an efficient and accurate method of tying known geology from a borehole given<br>in depth to the surface seismics ection presentedin time. The VSP enablest he geophysicistt o directly observet he<br>effects of the geology on the seismic wavelet generated at the surface. At each geological interface the resulting<br>transmissionr,e flection, conversion and attenuationc haracteristic of the seismicw avelet can be observed directly<br>from a VSP. Much like common depth point (CDP) reflection techniques VSP’s have been adapted from advances<br>in petroleum exploration.<br>VSP data follows a similar processings equenceto CDP data with stepss uch asg eometiy, first break picks,<br>deconvolution, and stacking. VSP data also has exclusive processing steps such as removal of down going waves<br>and enhancing upgoing waves. WELLPRO, licensed by GENIX Technology Ltd., was used to process the VSP data.<br>Displaying VSP data for interpretation includesm ergingw ell logs (measuredin depth) andt he processedV SP along<br>with a synthetic seismogram into a composite known as an L-plot. VSP data collected by the Geologic Survey of<br>Canada (GSC) as part of a regional hydrogeological investigation of the Oak Ridges Moraine, north of Toronto,<br>Ontario, are used as examples in this paper. Synthetic traces were generated by doing a 140 ms corridor stack of the<br>processedV SP andc an be directly correlated with surfaces eismicd ata acquiredn earby. The VSP verified the<br>existence of three reflectors at approximate depths of 45 metres, 68 metres, and 88 metres and also produced a<br>velocity profile based on depth and one-way travel time, This enables an exact time versus depth interpretation of the<br>surface seismic data at this location.