Abstract: Method and apparatus for generating data and analyzing the same to determine fluid depth in a well. A gun assembly includes a pressurized chamber for initiating an acoustic pulse and a transducer for measuring pressure variations. The gun assembly is mounted on a well casing at the top thereof. An acoustic pulse is initiated and reflections from tubing collars, well equipment, perforation zones and the fluid level surface are detected by the transducer and converted to an analog signal which is digitized and stored in a memory. The stored data is processed to detect the fluid pulse reflection in view of a set of preselected pulse criteria. Acoustic pulse velocity is calculated by correlating the tubing collar depths, which are stored in the memory, with peaks in the acoustic log which indicate a corresponding tubing collar.