Two-pulse tracer ejection method for determining injection profiles in wells

This patent describes a method of tracer logging to determine the injection profile of a well, comprising the steps of: injecting a first slug of tracer material into a carrier fluid at a location above any point of fluid exit from a well bore; injecting a second slug of tracer material into the carrier fluid so as to be a known distance from the first tracer slug; moving a tracer material detector through the slugs to determine the distance between the two tracer slugs at a known depth in the well bore; and calculating the amount of fluid exiting the wellbore based upon the distance determination