PRODUCTION LOGGING: OVERVIEW, BENEFITS & APPLICATIONS

As world oil reserves dwindle and energy consumption increases, there is an ever increasing need to optimally drain hydrocarbon reservoirs, such that every drop of recoverable hydrocarbon is extracted. Discovery of new oil fields is becoming rarer and there is a general move by operators to go back to the old wells that are declining in production to see how they can be worked over in order to increase hydrocarbon production.

Reservoir monitoring via pulsed neutron and production logging are two key tools that are used to diagnose the well production problems, discover bypassed hydrocarbon and monitor the production pattern with a view to efficiently drain the reservoir and avoid reservoir damage or water/gas conning. Traditional production logging data is acquired in order to quantify the different phase contributions, identify producing perforations and delineate water entry points amongst other uses.

Production log (PL) data can be used to address the problems highlighted above. In subsequent articles, we would take a look at the different sensors that make up a PL tool string and how the data acquired from these sensors are used to optimize production. We will also look at the slightly more complex array production log tools which are used for deviated to horizontal wells. We would go further to explore how taking a new perspective on PL data can give insights to molecular fluid behavior and help us better characterize the reservoir.

Sent in by Chinwendu Mogbo, an expert in cased hole petrophysics.