3-D seismic imaging of complex intrusions

Hans-Henrik Westbroek, Robert R. Stewart

The goal of this research is to assess the feasibility of using 3-D seismology for the prospecting and delineation of ore bodies. Since 3-D seismic surveying has been successfully used to define many complicated geologic structures in the oil and gas industry, it would seem to be a very promising survey for hard rock environments. Due to the complexity of the structure, accurate migration of the data is critical for proper interpretation. The initial phase of this research is to compare 2-D and 3-D migration techniques on physical modeling data obtained from an extremely rugose target.

A copper nugget was used as the target. The data obtained from the model showed many strong, heavily scattered reflections from the surface of the nugget. 2-D migration proved to be quite successful in delineating the bulk dimensions of the nugget and showing the surface profile. We anticipate that the 3-D migration will provide a more accurate image especially in terms of detail along the surface of the nugget. More structural information will be attained by taking time slices through the 3-D data volume.