Gasch & Associates of Rancho Cordova, California, wanted to provide their clients with a detailed rippability study for a housing development. The only data input used to produce the velocity model was the first arrival travel-time data and array geometry. No other a priori data were used.
This is a velocity model from one of the lines. As you can see, SeisOpt® @2D reveals both lateral and vertical velocity gradients in great detail. In fact, the petroleum industry uses our software for near-surface velocity static corrections because of the detail in which near-surface velocities are revealed. Gasch & Associates stated that their clients appreciated the detail revealed by these velocity models. Much better than the typical ”layer-over-a half-space” that most rippability studies produce. Ground was opened, and the models proved to be quite accurate. SeisOpt® @ 2D provides users with a much more sophisticated and realistic picture of the subsurface. There is no need to ”force” layer cases where there may only be a strong gradient. There is no curve fitting, no ray tracing, no need to make guesses on the structure of your field area while you are analyzing the data. There is no subjective information required as input for SeisOpt® @ 2D.
SeisOpt® @ 2D let’s you know if your target has been properly sampled prior to leaving the field, which can save enormous amounts of time and money. It produces a hit count plot that shows you how many rays have sampled each discrete point within your study area. If you look at some of the other examples at our site, you will also see how SeisOpt® @ 2D can either interactively or automatically optimize your seismic data acquisition array to be sure your target is properly sampled prior to leaving the field. In this example, notice the how high velocity areas affect the behavior of rays in the subsurface. Observing the way the rays are behaving below your feet, while you are still in the field, is quite enlightening and sometimes very surprising.