Steering Migration with Diffractions in Seismic Exploration for Hard Rock Environments

Abstract

Hard rock seismic exploration normally has to deal with rather complex geological environments. These types of environments are usually characterized by a large number of local heterogeneities (e.g., faults, fracture zones, steeply dip interfaces). The seismic data from such environments often have a poor signal to noise ratio because of the complexity of hard rock geology. In such situations, the processing algorithms that are capable of handling data with a low signal/noise ratio are essential for a reflection seismic exploration. In this paper we describe an alteration of the 3D Kirchhoff post-stack migration algorithm that utilizes coherency attributes obtained by the diffraction imaging algorithm in 3D to weight or steer the main Kirchhoff summation. We apply the method to a 3D synthetic model with a presence of high level of random noise; and test the algorithm on the 3D seismic volume acquired on a mine site located in Western Australia.