Early hydraulic fracturing completions in the Vaca Muerta Formation in central Argentina have incorporated the use of conventional fluid systems such as linear and crosslinked guar-based polymers. Within the past few years, however, the benefits of viscosifying friction reducers (VFR) have been demonstrated in the industry, predominantly within the United States. The objective of this project was to trial the VFR fluid technology in fracturing operations in this area for potential use for full field development.
Positive laboratory test results led to a field trial using this technology, during which several benefits of the VFR fluid system began to emerge. Operational efficiency was an early success, including a reduction in the quantity of chemicals on location, more simplified pumping schedules, and low pumping pressures. Secondly, significant cost savings were realized compared to previous fluid system packages. Finally, positive production results were observed, leading to the decision to incorporate this technology into full field development operations. This paper will review the results of the stepwise evaluation process along with a focus on the economic benefits and well production from the development phase evaluation project.
The area of operations for this project is shown in Figure 1. Within the Neuquén Basin, Pan American Energy operates in four areas which are active for tight gas as well as shale oil and gas. The field trial described in this paper took place in the Aguada Pichana Oeste block in the western part of the area, while the development project took place in the Lindero Atravesado block in the east, near to the Mari Menuco reservoir. Within the Lindero Atravesado block, the El Chanar deposit corresponds to the first development of unconventional shale oil from the Vaca Muerta in this block.
Over the past four to five years, polyacrylamide-based viscosifying friction reducers (VFR) have become a standard fracturing fluid system for many operators in the oil and gas industry. Industry publications (Van Domelen, et. al, 2017; Hazra, et. al, 2019; Dahlgren, et. al., 2018; Ba Geri, et. al, 2019) and case histories have highlighted the benefits of this type of fluid system over conventional guar-based fracturing fluids. Those benefits include:
• Cost Reduction and Simplified Logistics
• Viscosity Development at Low Concentrations
• Efficient Proppant Transport
• High Fracture Conductivities and Enhanced Well Production