A system and method for locating subsurface diffractors. The method operates on two-dimensional (2-D) seismic data that includes one or more 2-D seismic lines. The 2-D seismic data may be preprocessed to enhance diffracted energy. For each hypothetical diffractor location in a set of hypothetical diffractor locations, the method involves analyzing at least a subset of the seismic traces of the one or more 2-D seismic lines, in order to compute a value indicating an extent to which those seismic traces contain diffraction arrivals consistent with the hypothetical diffractor location. The method may further involve generating, storing and displaying an image (or map) based on the computed values. The image may illustrate areas of high, intermediate and low diffraction, and may be used to assess the formation.