@article{eage:/content/journals/10.1111/j.1365-2478.1977.tb01195.x, author = "URSIN, BJØRN", title = "SEISMIC VELOCITY ESTIMATION*", journal= "Geophysical Prospecting", year = "1977", volume = "25", number = "4", pages = "658-666", doi = "https://doi.org/10.1111/j.1365-2478.1977.tb01195.x", url = "https://www.earthdoc.org/content/journals/10.1111/j.1365-2478.1977.tb01195.x", publisher = "European Association of Geoscientists & Engineers", issn = "1365-2478", type = "Journal Article", abstract = "Abstract The accuracy of the two most common arrival time functions used in seismic velocity estimation is investigated. It is shown that the hyperbolic arrival time function is more accurate than the parabolic arrival time function for a horizontally layered elastic medium. An upper bound on the difference between the two arrival time functions is given. A maximum‐likehood detector for estimating the arrival time of the signals is given. For the signal‐in‐noise model that is used the maximum‐likelihood detector is equivalent to a least‐squares detector which corresponds to using the signal energy as coherency measure. The semblance coefficient corresponds to a normalized least‐squares detector. The semblance coefficient is very similar to a filter performance measure that is used in least‐squares filter design.", }