Abstract: The method of the invention makes it possible to determine the hydrocarbon flow rate Qhe in an oil well in production, by causing data acquisition apparatus to pass along the well once only, the data acquisition apparatus being provided with local sensors making it possible to distinguish between water and hydrocarbon. During the single pass, the hydrocarbon bubble count Bc per unit time, the water holdup Hw in the fluid, and the flow section A of the well are measured.

Abstract: A method for evaluating the quality of the cement surrounding a borehole casing is provided. The method generally comprises obtaining signals which were recorded by a CET tool known in the art, and processing the signals by: dividing each signal into particularly defined time windows; determining absolute magnitudes for each signal which are functions of the energy of the signal in the respective windows; determining normalized magnitudes for each signal from the absolute magnitudes and normalization parameters; and evaluating the quality of cementation as a function of the fact that the normalized magnitudes for each signal obey a predetermined law, and as a function of the relationship between each normalized magnitude and a pair of threshold values respectively associated therewith.According to another aspect of the invention, information obtained from a CBL tool known in the art is compared to the information gained from the CET tool.