Determining the Number of Contributing Fractures in Shale Gas Wells with Production Analysis and Proppant Tracer Diagnostics

摘要

As expansion into unconventional reservoirs continues, one of the key drivers of well performance has become completion efficiency. Much of this efficiency centers around finding the completion strategy that effectively drains the entire lateral in a horizontal wellbore. Different fracture spacing and perforation schemes have been attempted to try and accomplish maximum coverage with minimal interference between stages. However, even as fractures are planned with a particular spacing, there is no guarantee that every perforated interval will lead to a productive fracture. One of the key questions has been: How many of the fractures are actually contributing to production? Numerous authors have developed methods for estimating this number, and a small set of diagnostics tools are currently being used in the industry to evaluate fracture placement. In production prediction workflows the number of contributing fractures is estimated using data that are readily available, such as completion designs, fracture propagation models, or production profiles.