We constructed a synthetic interval velocity model, and then modeled a CMP gather using a finite difference code, Figure . We then picked RMS velocities and attempted to estimate our interval velocity. As Figure shows, we did a very good job of recovering the correct interval velocity.
synthetic-data
Figure 6 Modeled synthetic data. |
synthetic
Figure 7 Initial interval velocity, picked RMS curve, and inverted interval velocity curve. |
Using the same dataset (Figure ) we introduced some low-energy noise to our velocity scan and then attempted to invert back to our interval velocities. As Figure shows, even with the grossly inaccurate RMS picks at approximately 1.5 seconds we were still able to recover a reasonable interval velocity curve.
gap
Figure 8 Left panel, RMS picks overlaying semblance scan with noise introduced at approximately 1.5 seconds. Right panel, the resulting interval velocity curve, the curve without the bad data, and our bad-data RMS curve. |
xvals
Figure 9 Our preconditioned variable for the continuous case. |