Operator faced low fracture conductivity and proppant flowback challenges

The Volga-Urals basin is one of the oldest and largest oil-producing regions in western Russia. Today, after decades of prolific productivity, most of the region’s Devonian reservoirs are depleted, requiring hydraulic fracturing treatments for economic production.

While fracturing is a standard completion method for wells producing from Devonian formations throughout Russia, the operator quickly discovered that wells in the Orenburg region responded differently. The depleted reservoir pressure and multiphase flow led to poor fracturing fluid efficiency and proppant flowback issues. To combat premature screenout, the operator used large pad volumes and special fluid-loss additives. However, those techniques drastically limited production.

Channel fracturing and unconventional proppant increased stimulation effectiveness

To overcome poor fracture conductivity, the operator decided to try stimulating 20 wells with the HiWAY flow-channel fracturing technique. Schlumberger used pulsed pumping techniques and engineered fibers to create stable, open flow channels within the fracture.

After initial success with the HiWAY technique, Schlumberger recommended using RodPROP high-aspect- ratio proppant in the final stage to maximize near-wellbore conductivity and enhance proppant flowback control in the 20 wells. Made up of high-strength cylindrical particles, the unconventional shape of RodPROP proppant forms a consolidated proppant pack with improved permeability and stability compared with conventional proppant.

Technology combination increased average productivity by 99% in mature reservoir

A production study was performed for the first 20 wells treated with HiWAY technique and 32 wells using conventional fracturing techniques revealed that, on average, wells treated with HiWAY technique and RodPROP proppant had 99% higher productivity than the closest offset wells, verifying effective performance in treating these depleted Devonian formations. In addition, the treatments eliminated screenouts and proppant flowback issues, allowing the operator to design advanced fracturing treatments with larger proppant mass, higher proppant concentration, and larger propped width.