Time-to-depth conversion and seismic velocity estimation using time-migration velocity

Synthetic data example

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Figure 2. Synthetic test on interval velocity estimation. (a) Exact velocity model. (b) Dix velocity converted to depth. (c) Estimated velocity model and the corresponding image rays. The image ray spreading causes significant differences between Dix velocity and estimated velocity.

Figure 2a shows a synthetic velocity model. The model contains a high velocity anomaly that is asymmetric and decays exponentially. The corresponding Dix velocity mapped from time to depth is shown in Figure 2b. There is a significant difference between both the value and the shape of the velocity anomaly recovered by the Dix method and the true anomaly. The difference is explained by taking into account geometrical spreading of image rays. Figure 2c shows the velocity recovered by our method and the corresponding family of image rays. An analogous 3-D example is provided in (Cameron et al., 2007).

Time-to-depth conversion and seismic velocity estimation using time-migration velocity