Underpressure Occurrence In Greenfield: Deciphering Pressure Anomalous Through Integrated Subsurface Evaluation

Underpressure is observed in a green gas field offshore Malay Basin at selected reservoir intervals prior to encountering overpressure zones. Multiple data has been utilised to understand the depleted hydrostatic gradient observed which is usually due to production but not plausible in T field as there is no neighboring producing field within more than 30km. Pressure plots suggest that anomalous underpressure due to osmosis hypothesis due to difference in salinity which affects the solute concentration across the reservoir intervals. Since only 2 wells are available in the field but has high degree of consistency between data representation and interpretation, the underpressure is a risk that needs to be accounted to prior to drilling operation to mitigate any drilling risks. All future development wells should acquire pressure data especially in the underpressure reservoir to further understand the extend of depleted pressure laterally in the main structure and possibly, in the undiscovered fault block too.