Use Ray-Based Modeling Methods to Plan, Analyze, and Control Subsalt Imaging

Though ray tracing in its standard forms is not able to produce complete synthetic seismograms, as may be required for processing tests, it may be used in completely different manners and thus providing other type of information useful for the industry. A now classic example is the use of ray-based illumination studies to test surveys for subsalt imaging, where the output are various maps of attributes along given horizons, e.g., so-called hit maps (reflection points), etc. This is especially interesting when testing various survey azimuth geometries. Another technique allows to find azimuth and offset ranges of a survey to illuminate given points on a horizon, e.g., below a salt dome. Going further, an efficient method can also generate migration amplitudes for the same horizons without explicitly generating synthetic seismograms. In a more local approach, a PSDM simulator uses ray-generated Green’s functions to simulate 3D PSDM cubes, including 3D illumination and resolution effects. Such simulated PSDM results allow quickly testing subsalt imaging effects on detailed reservoir targets, without needing to compute synthetic data and process them.