Published: 02/12/2018
Published: 02/12/2018
To optimize stimulation of plug-and-perf wells in the Nemaha Osage formation, an operator experimented over the last several years with small changes in proppant concentrations and volumes, pump rates, and fracturing fluids. By the beginning of 2017, the operator had migrated to hybrid fracturing designs combining conventional slickwater with guar-based linear gel.
However, the operator was aware of technical studies from the Stim-Lab Proppant Consortium and from other operators indicating that hybrid fracturing designs, even with low guar-polymer content, can limit well production. Therefore, the operator sought new options to optimize stimulation design.
Schlumberger proposed replacing the hybrid fracturing fluid design with viscous slickwater to enable more aggressive proppant designs.
Viscous slickwater is an engineered fracturing fluid that combines the operational simplicity and cleanup of conventional slickwater with the proppant transport benefit of a more viscous linear or crosslinked guar gel system—without the guar residue. With viscosity as high as 100 cP and minimal fluid friction, viscous slickwater fluids enhance proppant-carrying capacity and enable aggressive pumping schedules. The simple fluid design also eliminates the need for a hydration unit, which reduces operational footprint and complexity.
For the Nemaha Osage formation wells, the viscous slickwater fluid enabled a design that doubled the volume of proppant in each stage and increased the maximum proppant concentration from 1.25 ppa to 3.5 ppa. Changes to the casing program also enabled an increase in pump rates from 97 to 110 bbl/min [15.4 to 17.5 m3/min] and reduction in average stage spacing from 240 to 140 ft.
After stimulating seven wells using the new design, the operator reported a fieldwide production improvement of 35% in barrels of oil equivalent, including gains in both oil and gas production. The increases directly impacted the company’s business, increasing returns by as much as 30%.
In addition, eliminating the hydration unit reduced the operational footprint and improved overall service efficiency.
Challenge: Improve oil and gas production and completion and stimulation efficiency in the Nemaha Osage formation.
Solution: Redesign the stimulation strategy by
Results:
