3D Seismic Surveys for Shallow Targets

A high-resolution 3D seismic survey was undertaken to map shallow stratigraphy near Calgary, Alberta. The survey was 500m x 300m in area, with shot and receiver lines in an orthogonal geometry using 50m line separation. Shots and geophones were spaced at 10m intervals along source and receiver lines, respectively. The surface source used was an 18,000lb EnviroVibe sweeping over a 10Hz to 180Hz range. The survey yielded excellent reflections with a dominant frequency of 50Hz. One high-amplitude west-dipping reflection, occurring between depths of 250m and 450 m, was mapped over the survey area. The project demonstrates the efficacy of reflection seismic surveys for shallow (100m – 500m) targets