Historically, the main reason for running production logs (PLT) is to obtain the downhole flow profile, which is needed either for reservoir monitoring or to decide appropriate remedial action in production wells. This emphasis on calculating the downhole flow profile with the spinner and hold up tools tends to reduce the focus on the interpretation of the other production logging sensors that are normally recorded in the production logging string, such as gamma ray, pressure, and temperature. The authors of this paper have placed particular emphasis on the importance of these additional sensors and have highlighted how much extra information can be obtained through the proper interpretation of these sensors.

In this paper we present seven cases that address the importance of interpreting these other sensors:

Case 1: Gamma Ray (GR) interpretation that helped to detect the presence of radioactive material in the hydrocarbon, and to understand the relation between the chemical diverters that were used during acid stimulation and the accumulation of the radioactive materials in the wellbore during the shut-in conditions.

Case 2: Qualitative interpretation of the spinner data response can help to identify the presence and nature of solids, and/or viscous fluid, and their relation to the performance of unproductive perforations.

Case 3: Downhole fluid density, computed from pressure data, was used to detect the source of potential surface water production. This helped to design a successful water shut-off job that was performed later.

Case 4: Using pressure data to get the pressure, permeability, and skin in multi-layer wells.

Case 5: Caliper comparison to confirm the impact of acid stimulation on borehole shape.

Case 6: Gas holdup and pressure measurements were used to verify the oil bubblepoint pressure value.

Case 7: Comparison of pressure measurements between surveys to understand horizontal well production profile behavior.

Based on this work we would like to introduce an integrated/practical workflow for production logging interpretation that honors data from all the acquired sensors.