Fracture detection using scattered waves in the angle domain

Abstract

The singly and multiply scattered waves generated from interfaces of a fractured medium have strong energy, and their propagation directions contain information of fracture parameters. To exploit the useful information in the scattered waves, a fracture scattering imaging method is developed based on reverse time migration and angle decomposition. In this method, a fracture-parameter-related local image matrix is constructed in the angle domain based on the relation between the fracture parameters and the propagation angle of the scattered waves. The distribution of the scattered waves in the proposed image matrix can be used to invert for fracture parameters and identify the energy of scattered waves. Images of the fractures can be obtained by summing up the energy of the scattered waves from the proposed image matrix. Synthetic and field examples are provided to determine that the new method is effective in migrating the fracture-scattered waves at the correct spatial position and accurately extracting fracture parameters.