Sustained economic and effective post-fracture production in the Eagle Ford is a multi-variant process. Optimal post-drill well productivity is a function of fracture mechanics, proppant selection, and frac fluid characteristics. A crucial variable to effective fracture conductivity is residual frac fluid damage, which is illustrated by production results. In this paper, case studies target the relationship between frac fluid selection and well performance by documenting the application, fracture design, fluid description, production results, and production analysis of subject wells compared to offsets using a new low damaging frac fluid (LDFF).
Following the fracturing process of organic source rock reservoirs, a large percentage of fracturing fluid is typically not recovered during production. This post-fracture reservoir system is often referred to as the " invaded zone." Fluid mobility occurring within the invaded zone is caused by differential pressure from the wellbore to the fracture system tip. Residual fracture fluid is caused by ineffective differential pressure within the invaded zone. Enhancing this pressure drawdown from the wellbore to the tip can be achieved by reducing residual fluid damage using the LDFF instead of conventional guar fluid systems. Increased frac fluid recovery using the LDFF has been documented and is presented in this work.
LDFF is a +90% regained conductivity, water-based, crosslinked fluid system that has replaced the use of a 40% regained conductivity, guar-based crosslinked fluid system. Fracturing with this fluid system began in 2012. By September 2012, more than 1,600 fracture treatments were completed within the Bakken, Niobrara, Cline, Wolfberry, and Eagle Ford organic source rock reservoirs. The LDFF has been successfully used at depths ranging from 3,500 to 11,500 ft with bottomhole static temperatures (BHSTs) ranging from 120 to 330°F.