GNGTS 2013 - Atti del 32° Convegno Nazionale

If the energy of the reflections has been correctly removed in the dip filtering step it is possible to emphasize only the true diffractions with a low computational effort. This is also a drawback of the algorithm: also the residual reflections which survive to the dip filtering step (e.g. due to an incorrect dip estimation) could be emphasized through the application of the mask, being coherent events as well. Example. As an example we show the synthetic Sigsbee 2A dataset released by the SMAART JV consortium. This model contains a sedimentary sequence broken up by a number of normal and thrust faults. In the sedimentary sequence are embedded two dozens of point diffractors, regularly Fig. 1 – Migrated image of the Sigsbee 2A synthetic dataset: image 1-a is a zoom of the zone with the diffractor point. The black arrows b c and d point to the location of the dip-angle common image gathers of images 1-b, 1-c and 1-d respectively. Fig. 2 – From left to right: first, a dip-angle CIG located exactly in correspondence of two diffractor points. Second, a dip-angle CIG in the same location after removal of reflection via dip-filtering. Third, local dip coherency estimated on the previous CIG. Fourth, enhancement of diffraction on the second dip-angle CIG. 74 GNGTS 2013 S essione 3.1