Manage or shut off water and gas production with application-specific permeability modifiers, chemical blocks, or cements.
Published: 10/10/2012
Published: 10/10/2012
High sand and water production—and up to 15% clay content—often restricted productivity from the Cangapi formation, an unconsolidated, sandstone reservoir. To overcome migrating fines and discontinuous pay zones, Schlumberger applied ISO-AllPAC† sand-control screens with Alternate Path technology. However, some wells were still producing under potential after gravel packing.
To determine the best solution, Schlumberger performed core flow testing and VirtualLAB geochemical simulation. After careful analysis, the team recommended matrix acidizing stimulation with OCA organic clay acid. This treatment fluid was ideal for its ability to remove damage and stabilize fines with minimal risk of forming damaging precipitation such as hydrated silica gel. Schlumberger also recommended MSR mud and silt remover to reopen clogged pathways and OilSEEKER acid diverter to prevent treatment fluid from entering possible water-bearing zones. Nitrified fluids were used to enhance performance and cleanup.
NODAL analysis showed poststimulation production of 10.5 MMcf/d with a 54⁄64-in choke. This was significantly higher than offset wells. The success of the treatment led the operator to use ISO-AllPAC screens with OCA stimulation fluid on subsequent wells.
Challenge: Stimulate gas flow through the gravel pack completion to reduce sand and water production in a depleted, unconsolidated sandstone reservoir.
Solution: Use OCA organic clay acid system with OilSEEKER acid diverter to achieve deep, live-acid penetration, plug water-saturated zones, and stabilize fines.
Results: Realized sustained gas production rates of 10.5 MMcf/d with a 54/64-in choke, as confirmed by NODAL production system analysis.