A well collar counting methodology is provided comprising first obtaining acoustic pulse data from a well and then digitizing and storing the amplitud e-versus-time signal for subsequent processing. The raw signal is processed by applying a Wavelet Transform thereto for producing multiple resolutions of the signal, preferab ly four, at least one of which has a transformed signal resolution sufficient to distinguish r eflections emanating from collars, and one of the coarser resolutions having a transfor med signal resolution sufficient to distinguish reflections emanating from the fluid su rface as kicks. The fluid surface kick and repeat kicks are determined by performing multi-r esolutional analysis of each maximum, at the coarser resolution, as synchronized against the successively finer resolutions and compared as being significant with respec t to adjacent maximums. Tubing collars are then counted at a finer resolution, as being re flection maximums counted in the interval between the wellhead and the kick, irrespec tive of tubing joint length or collar frequency. Direct collar counting, interpolati on and extrapolation of collars is performed.
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