Challenging downhole environments require an unconventional integrated production logging solution that is reliable and efficient. Production logging provides information during production operations and beyond. However, conventional production logging in extended reach horizontal wells, equipped with Electric Submersible Pumps (ESPs), is complicated, as the locations of water- and oil-producing zones are uncertain due to the impurity of the borehole, caused by the presence of debris and thick material. Such downhole conditions affect the production logging tool sensors and lowers the measurements resolution.
Downhole conditions can present challenges for casedhole and openhole evaluation programs, and each horizontal well presents a different complexity. The technique relies on the combination of the advanced multiphase production logging tool (AMPLT) and the pulsed neutron logging tool (PNLT). Measuring the flow rate downhole, PNLT data were acquired to complement the AMPLT spinner data when flowing at both high and low choke settings and shut-in surveys. The acquisition procedure is to allow unfavorable conditions to be logged at varying flow rates, to identify the fluid flow profile.
We have studied wells equipped with ESPs to gain insight into the job planning, deployment and integration of results for horizontal well production profiling. The examples illustrate the optimization done during the job that led to successful execution. The first example is an openhole horizontal well logging case using conventional logging solution. This is followed by the second well, showing the effect of harsh environment in the openhole section on the logging tool and sensors. The last two field examples were logged recently, and the measurements and interpretation techniques are analyzed in detail in the paper.
This innovative production logging solution has resulted in the successful assessment of downhole fluid entries with high confidence and safe operation despite the challenging downhole environment. Such logging is necessary to understand reservoir fluid dynamics, which is fundamental for effective reservoir management and planning more efficient workovers.