Structural uncertainty of time-migrated seismic images |

scan,scan2
Velocity scan at
10 km image gather. The curve in (a) corresponds to the
automatically picked velocity trend. The curves in (b) identify an
approximate range of velocity uncertainty around the picked trend.
Figure 6. |
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Figure 6a shows a semblance scan produced in the process of velocity continuation. A common procedure in migration velocity analysis is picking a velocity trend from the semblance, either manually or automatically. In this example, we use automatic picking with the algorithm described by Fomel (2009).

While picking may select the most probable velocity function, its
probability is less than 100%. If we view normalized semblance as a
probability distribution and determine a confidence interval
corresponding roughly to one standard deviation, it provides an
approximate range of uncertainty in velocity determination. This range
is shown in Figure 6b and computed according to

Structural uncertainty of time-migrated seismic images |

2013-12-07