A gas condensate field development in the offshore Caspian Sea experienced monitoring challenges and costly operations. In regular field-wide surveillance it is a challenging task to evaluate the numerous well monitoring options on the market, such as production logging, permanent downhole gauges, and distributed temperature sensing along the wellbore. These solutions require wellbore interventions and introduce operational risk during well logging or completion installation risk when fiber is installed. Permanently installed inflow tracer technology is an alternative monitoring solution which avoids the above-mentioned risks but still obtain valuable inflow information concerning well performance over several years.
An appraisal well in the field was selected to pilot inflow tracing technology for assessment of reserves and productivity, for the first time in the Caspian Sea. Multiple sampling campaigns to capture the data was incorporated into a well testing programme to complement the pressure transient data collection and interpretation. The inflow tracer interpretations were successful in providing additional insight towards clean-up efficiency and flow distribution between zones. The latter was verified later by production logging, strengthening confidence with inflow tracer technology.
The application of the permanent inflow tracers has proven to be a viable alternative to other well monitoring solutions without any risk and will become an effective long-term monitoring solution for planned production wells in the field development.