PEMEX saw unexpectedly high water production from new well in Kuil field
While drilling an offshore well in a high-temperature, naturally fractured carbonate formation, PEMEX encountered severe lost circulation, losing more than 12,000 bbl of mud into the formation. PEMEX controlled these severe losses by adding CaCO3 solids to the oil-base drilling fluid, however the lost circulation material resulted in formation damage. Testing showed an estimated skin value of +10 on a 1 ½-in choke, but initial oil production reached 5,880 bbl/d. Shortly, water production grew to 28%, impeding oil flow. To increase oil production and reduce water cut in this critical well, PEMEX partnered with Schlumberger for a matrix acidizing treatment.
OilSEEKER acid diverter plugged high-water-cut zones
Schlumberger lab engineers performed extensive compatibility tests with drilling mud and oil samples to recommend a suitable acidizing plan for the well. Schlumberger applied OilSEEKER acid diverting agent to selectively stimulate hydrocarbon zones. Then, a blend of organic acids were pumped to penetrate pay zones. Nitfrified fluids were used to enhance performance and well cleanup.
PEMEX increased oil production 45%, realized additional USD 134,000 per day
Skin value decreased to –2, indicating enhanced well productivity. Post-treatment NODAL analysis showed oil production rates of 8,579 bbl/d with 1.6% water cut through a 1 ½-in choke. The 45% production increase was valued at approximately USD 134,000 per day.
“OilSEEKER diverter has made an important contribution to our matrix stimulation treatments in naturally fractured, high-productivity wells,” said Nemesio Miguel-Hernandez, Design and Evaluation Coordinator, PEMEX. “In the last two years, the stimulation jobs conducted with OilSEEKER diverter have consistently increased oil production while reducing water cut.”
As a result of the matrix acidizing treatment, Schlumberger became the preferred stimulation services provider for new PEMEX wells throughout the Kuil oilfield—and the region.