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MBH-MDA are dry gas fields situated in offshore Indonesia. Both fields are producing from Globigerina foraminifera’s fossil-dominated limestone reservoir. Good quality grainstone to poor quality argillaceous limestone are found in this reservoir, where good quality reservoir is correlated with low rock consolidation. Limited benchmark in handling Globigerina limestone reservoir has led to uncertainties and assumptions during the early development phase. Paramount takeaways include post-drilling result, clean-up and initial production strategy, reservoir surveillance, and production optimization.

Rigorous reservoir management and data acquisition plan are extended for managing this unconventional formation. Acidizing was performed as part of clean-up sequence in selected wells to improve deliverability. All wells are equipped with fiber optic permanent downhole gauge (PDHG) and wet gas flowmeter (WGFM). Solid production due to low rock consolidation is expected to occur at late production life, therefore premium mesh screen and acoustic sand monitoring equipment are installed as part of solid management. Routine and non-routine data acquisition are scheduled to understand the reservoir behavior better. These best practices are essential to ensure optimum production from each wells.

Post-drilling result showed up to 30% increment in gas well deliverability, mainly driven by acidizing and good reservoir properties per se. During clean-up, less expected solid production was observed among wells with the best reservoir properties even with small drawdown pressure. Those wells are currently on rate restriction despite of their high deliverability, due to unexpected solid production found at the surface in early production, proper desander was installed at the surface to mitigate future sand production potential.

Another outstanding issue is coming from the data quality of fiber optic PDHG installed. Pressure transient analysis is not feasible to be performed due to 20-30 psi erratic data recording. Lot of efforts has been put into the data processing to provide relevant analysis; however no convincing result was obtained.

Surface solid handling and modified PDHG installation are proposed for the upcoming analogue field development. Currently, only selected the most reliable data available are used and integrated to come up with sound reservoir analysis for subsurface understanding and production optimization plan.

Invaluable lesson learned and best practices from developing the unique and unconventional Globigerina limestone reservoir can be applied and replicated to analogue fields in purpose of understanding the well behavior and optimizing deliverability from this reservoir.