Logging Solutions for Completion Optimization in Unconventional Resource Plays
Successful United States shale plays are often used as a template for the drilling and completion strategies for newly emerging shale plays around the world. However, studies of production logs in the Barnett Shale, the Marcellus Shale, and the Eagle Ford Shale have shown that a significant percentage of perforations clusters are not producing quantifiable amounts of fluid or gas(Miller, 2011). Case studies designed to address this have shown that addressing the heterogeneity experienced around the wellbore (Wutherich, 2012) in combination with more focus on landing and staying in the best quality reservoir rock (Baihly, 2010) lead to more productive wells with a higher degree of perforation performance.
Many operators face the challenge of is incorporating a completion optimization workflow into their completions that is both technically effective and cost effective. The desired completion system is one that incorporates as much information as needed for successful completion while being operationally unobtrusive. Refined techniques used to convey dipole sonic tools in cased laterals have been supplemented by a new generation of easily deployed tools capable of making density, neutron, resistivity, and sonic measurements in open hole. This gives operators a wide array of options that can fit into a completion optimization program.
This paper reviews the concept of optimized plug and perf completions as compared to the more frequently used approach of geometrically spacing stages and perforations. Reservoir quality and completion quality variables were used to design engineered completions in a multi-well study of Eagle Ford Shale wells. The study used a cost effective workflow that is repeatable and portable in order to increase the effectiveness of hydraulic fracture treatments. The workflow is shown to improve overall production and well economics by increasing perforation efficiency.