Velocity analysis using weighted semblance
نویسندگان
چکیده
Increasing the resolution of semblance-based velocity spectra, or semblance spectra, can improve the accuracy of normal moveout velocity estimates. The resolution of semblance spectra depends on the sensitivity of semblance to changes in velocity. By weighting terms in the semblance calculation that are more sensitive to changes in velocity, we can increase resolution. Our implementation of weighted semblance is a straightforward extension of conventional semblance. Somewhat surprisingly, we increase resolution by choosing a weighting function that minimizes semblance. Compared to conventional semblance, weighted semblance better distinguishes semblance peaks for interfering events.
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