Special Purpose Production Logging Fundamentals

This skill module focuses on interpretation of special purpose production logging techniques, namely noise logging, radioactive tracer logging, and distributed temperature surveys using fiber optic cables. Noise logging principles are covered and examples of using noise logs to identify fluid entry/exit points and leaks and to distinguish single-phase from two-phase flow are given. Radioactive tracer techniques are presented, and examples are shown for calculating flow rates in shut-in and flowing wells using slug tracking and velocity shot techniques. Instrumentation is covered for fiber optic temperature measurements and some examples showing how this works are given.

This skill module concludes with a lecture and an exercise on designing an integrated production logging program. Unlike conventional and array production logging measurements that can only sense what is happening inside the casing, noise, radioactive tracer, and temperature measurements can also sense some of what is happening behind the casing.