A fluid measurement system (10, 110, 210) and method of fluid mix determination over a sampling length (25) in a well bore (12). A pulse generator is run in the well bore from which is suspended a cable (24) with two conductors having a length equal to the sampling length. A high frequency pulse is injected along the cable and from the detected response average propagation velocities over the various reflections are used to determine the mixture of fluids. Embodiments are described which improve the determination such as using a cable with sections of alternating impedance, helically wound cable, providing multiple signal generators, incorporating a mathematical model, analyzing the analog signal response, providing a reference cable and incorporating an optical distributed temperature sensor.