The emerging Vaca Muerta Formation, located in the Neuquén Basin in Southern Argentina, is the most successful Unconventional Play outside the United States. The development of this Formation has started several years after the massive development of US Shale Plays, giving local operators the opportunity to incorporate lessons learned and best practices applied in other Basins.
Completion Designs are considered to play a key role to maximize the ultimate recovery in unconventional reservoirs. Fortunately, classic hydraulic fractures designs, legacy from conventional reservoirs, have rapidly evolved to modern designs, more suitable for unconventional reservoirs. From vertical wells with hybrid completion fluids to multi-fractured horizontal wells including High Density Completion (HDC) techniques, Engineering Completions (EC) and Variable Shot Clusters (VSC), US Shale experience has accelerated the learning curve in Vaca Muerta Formation. Design of Experiments (DoE) was used to leverage numerical models' capabilities and optimize hydraulic fractures designs. This contribution summarizes state-of-the-art completion techniques successfully applied in Vaca Muerta Formation.
Pan American Energy is leading the State-of-the-Art completion techniques executed in Vaca Muerta Formation using straightforward processes to make decisions and rapidly adopt lessons learned and best practices from US Shale Plays.
The subsurface team has played a key role leading the continuous improvement of completion designs. The stimulation team has applied operational excellence execution to make the improvements happen. A multi-disciplinary team between reservoir engineers, geomechanics and stimulation engineers is mandatory to successfully apply the Deming Cycle (Plan-Do-Check-Act) to hydraulic fractures designs.
It is important to mention, that not all techniques that were successfully applied in US Shale Plays are expected to be successful in Vaca Muerta Formation, from different rock properties to limited technology availability (i.e., oriented perforations, variable perforations diameter, etc.), the completion optimization process in this Formation is a unique challenge.
Since the first horizontal well drilled in Vaca Muerta (2011), hydraulic fracture designs have evolved significantly. More Proppant and Fluid Intensity was pumped in the most recent wells and reduced stage spacing were executed to evenly distribute the treatment along the well. Additionally, the standard deviation around design parameters increased from early 2019 as part of the optimization process that operators are looking for (Figure 1).