Improved analysis methods for radioactive tracer injection profile logging

Radioactive tracer logging has been used for many years to measure injection profiles. In this study, the tracer loss and velocity shot methods of radioactive tracer logging have been analyzed to develop guidelines for improved interpretation of these logs. In addition, tracer logging was simulated experimentally in a test pipeline to check assumptions made in the theoretical analysis. Among the conclusions drawn were that the tracer loss method is imprecise because of poor depth resolution and nonuniform mixing of tracer and that the velocity shot method is subject to significant error when fluid is exiting between detector locations. Finally, a new radioactive tracer logging method is proposed that may offer some advantages over current practices.