Production logging is a necessity in today’s deep and complex reservoirs, where high-production and extreme downhole conditions (including high pressure high temperature (HPHT), carbon dioxide, and hydrogen sulfide) require constant monitoring of well performance. This service can be combined with other cased hole logs, such as tubing evaluation and pulsed neutron, to establish a customized relationship between the fluid, wellbore, and completion properties. This process enables the construction of an instantaneous relationship between these three elements and determines the efficient production of each well.

This service integration was successfully applied in a deep gas condensate well in southeastern Bolivia. With more than 5200 m of total depth and a wellhead pressure of 5,500 psi, the operating conditions proved to be difficult. However, they proved ideal for the use of memory logging tools that, when deployed downhole with slickline wire, facilitated surface pressure control without risking log quality assurance/quality control (QA/QC).

Producing at a high flow rate (> 100 MMscf/d) from three reservoirs, the well required constant flow profiling and production follow-up. In addition, the presence of carbon dioxide in the gaseous stream provided opportunities for weakening the mechanical integrity of the completion through the onset of corrosional events. After running a production log, the client discovered an unexpected fluid entry point in the completion string, which was confirmed as an orifice with a subsequent tubing evaluation logging run. After reviewing the original production log, the client determined that the high flow rate from a particular formation had eroded a blast joint and created the orifice.

Running these services with memory tools reduced preparation time and operating costs. These benefits enabled the client to quickly acquire detailed information about the downhole condition of the well, improve the understanding of the relationship between reservoir and completion, and reduce production downtime and service costs.

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