Integration of FLAIR Service Enables Cost-Effective Reservoir Characterization | Schlumberger
Case Study
Malaysia, Asia, Offshore

Challenge: Offshore, multilayered HPHT reservoir required optimized sampling program to reduce risk and increase sampling recovery.

Solution: Acquire reservoir fluid properties from surface logging while drilling using FLAIR fluid logging and analysis in real time.

Results: Identified subtle compositional variations in fluids across several reservoir layers while drilling, optimized sampling and downhole fluid analysis program, maximized value of acquired information, and improved planning for future wells.

Products Used

Integration of FLAIR Service Enables Cost-Effective Reservoir Characterization

Continuous fluid typing while drilling enables optimized downhole sampling and maximizes information acquired in complex HPHT exploratory well.

Hostile downhole conditions required optimized sampling program

While drilling an HPHT (16,400-psi, 327-degF) exploration well offshore Malaysia, a major operator in Southeast Asia wanted to optimize its downhole fluid sampling and analysis program. A continuous fluid facies log along the entire drilling interval, covering all sands of interest, would improve selection of both the sample depths and the estimates of the likely fluid type. Minimizing risk and cost was a priority in this challenging environment, while maximizing the amount of information acquired while drilling was paramount for the project.

Cost-effective fluid typing while drilling

The FLAIR service was used to continuously analyze hydrocarbons extracted from drilling mud returning to the surface, providing a quantitative C1–C5 composition of the downhole reservoir fluid, and qualitative measurement in the C6–C8 range. Integration of the FLAIR service within an innovative workflow—including downhole fluid analysis (DFA) and pressure-volume-temperature (PVT) data—was implemented to provide a cost-effective solution for formation evaluation analysis.

Early identification of compositional variability improved downhole evaluation

FLAIR analysis identified subtle compositional variations with depth while drilling. Fluid families with a characteristic signature were identified—a detailed fluid distribution was then used to select depths for fluid sampling and DFA. The downhole data, in turn, was used to calibrate the fluid signatures, and subsequent PVT analyses of the samples further corroborated the results of the FLAIR service. The validated fluid signatures were then used to optimize evaluation programs, enabling both time and cost to be saved in future wells within the field.

overflow image
The reservoir fluid analysis workflow, comprised of FLAIR analysis, DFA, and PVT data.
overflow image
The fluid complexity is highlighted by the fluid facies log provided by FLAIR analysis (track 2). Red circles indicate the sampling depths suggested to the operator, based on fluid composition variations highlighted by the FLAIR service. The table shows the close correlation in the C1–C5 range between the FLAIR analysis and PVT results (C1f, C2f, etc. = formation fluid content; C45f = iC4f + nC4f + iC5f + nC5f).
Products Used

Share This