Carbonate formations required acid stimulation to become viable
The Volga-Ural region is one of Russia’s oldest and largest
resources—with more than 60 billion barrels of proven conventional
reserves. About 70% of all production in the region comes from carbonate
formations, which commonly require matrix acidizing and acid fracturing
stimulation. However, carbonate matrix stimulation in the region is
challenging. Every day, an operator in the Volga-Ural region faced depleted
reservoir pressure, difficult flowback, formation heterogeneity, and water cut
up to 60%.
Operator piloted FoamMAT service in seven depleted wells
To overcome extremely depleted formation pressure and kickoff
difficulties, the operator implemented a diverse portfolio of acidizing
technologies. After the operator applied conventional viscous diverters and
acid fracturing with little success, Schlumberger recommended FoamMAT foam
diversion service for matrix treatments. FoamMAT service uses a stable,
nondamaging diverting agent at 65% nitrogen foam quality downhole. After the
treatment, the foam breaks down into liquid and nitrogen, which enhances
flowback and kicks off the well to restore natural flow.
The operator decided to pilot the technology with bullheading placement
in seven wells ranging from 13,780- to 14,108-ft [4,200- to 4,300-m] TVD.
FoamMAT service helped increase well production by 440%
The wells that used FoamMAT service experienced a 440% increase in
production—nearly double the average production gained with conventional
acidizing techniques. FoamMAT service also reduced acidizing treatment cost by
decreasing the volume of liquid diverter needed. Due to the success of the
pilot, the operator now uses FoamMAT service in half of its acidizing jobs.