Case study
WaterSEEKER Water Control System Increases
Oil Production 244%, Reduces Water Cut 65%
Selective slurry system plugged water-producing zones in southern Mexico well
Challenge
Increase oil production and decrease
water cut, which had gone from 1,700 bbl/d
to 290 bbl/d and 0% to 70%, respectively.
Solution
Plug water-producing zones with the
WaterSEEKER* selective slurry system.
Results
Increased net oil production to 1,000 bbl/d
and reduced water cut to just 5%.
Mexico operator needed to revive oil production in high-water-cut well
Over the years, a southern Mexico well went from producing 1,700 bbl/d to just 290 bbl/d. The
water cut, which had increased from 0% to 70%, was reducing oil production and negatively
impacting well economics.
A production logging tool (PLT) showed three producing intervals—with the majority of the
well’s oil production coming from the 5,030–5,050 m interval. Due to rising oil-water contact,
the two deeper intervals and the lower portion of the third interval were invaded by water. The
PLT also showed a leak in the casing at 4,975 m that was producing massive amounts of water.
To save the well, the operator needed to selectively plug the water-producing zones as quickly
as possible. Schlumberger recommended the WaterSEEKER system, a miscible solvent slurry
squeeze treatment designed to control water production reliably, efficiently, and cost-effectively.
Selective cement slurry blocked water production
The WaterSEEKER system, composed of microcement suspended in miscible solvent, rapidly
hydrates and sets only when in contact with water. But, when the slurry comes in contact with
oil, it remains liquid and flows back up after treatment—leaving oil-producing zones undamaged.
To prevent the water-control system from activating in the tubing, solvent and oil-base spacers
were pumped before and after the treatment. First, Schlumberger thoroughly cleaned the intervals by performing an injection test using 10 m3 of xylene and 25 m3 of diesel. Once the wellbore
was completely free of water, the intervention team pumped 7 m3 of the WaterSEEKER selective
slurry followed by another 20 m3 of diesel. Lastly, to ensure adequate compressive strength
development, the well was shut in for 36 hours.
Oil production increased to 1,000 bbl/d with a 5% water cut
The WaterSEEKER selective slurry plugged all the water-producing zones with minimal
downtime. After the water control treatment, the operator realized a 65% decrease in
water cut and a 244% increase in oil production.
500
140
450
120
400
20
0
Pressure, psi
Volume, bbl
40
Diesel
displacement
300
250
Waterless
cement slurry
200
50
0
8
12
10
8
4
100
9
14
6
150
10
16
7
6
5
4
Rate, bbl/min
60
350
Pressure, TP
Density
Rate
Volume
Density, lbs/galUS
100
80
■
■
■
■
3
2
2
1
0
0
10:11:17 10:23:47 10:36:17 10:48:47 11:01:17
Time, h, min, s
www.slb.com/stimulation
*­ Mark of Schlumberger
Copyright © 2011 Schlumberger. All rights reserved. 11-ST-0110
Pumping chart of water control treatment with WaterSEEKER slurry.
Water Control