Argentina possesses some of the largest shale oil and gas reserves in the world and has the potential to benefit from the technologies currently used to extract unconventional shale resources in North America. Historically, Vaca Muerta resources were produced using vertical wells that were often stimulated in a few zones with plug-and-perf technology. Recently, operators started to adopt horizontal drilling and new multistage completion technologies to maximize access to the reservoir and increase production.
Although vertical wells are still popular, horizontal wells are gaining popularity in Argentina. Operators experimenting with horizontal wells are drilling longer laterals and are increasing the stage count within those laterals. Plug-and-perf is the typical completion system in horizontal wells; however, new technologies such as ball-activated sliding sleeve systems are being tested.
This paper will present the unconventional multistage hybrid completion of an exploratory well in the Neuquén Basin targeting the Vaca Muerta formation. The completion was comprised of 28 total stages: 13 open-hole, ball-drop sliding sleeve stages in the lower portion and 15 cemented plug-and-perf stages in the top portion. Disintegrating ball technology was used in conjunction with sliding sleeves so that post-frac intervention was eliminated in the deepest part of the well. The plug-and-perf stages were milled out after the fracturing treatment.
This well was the longest lateral drilled to date in Argentina at 2,016 meters (6,614 feet) and had the highest initial production rate of any well in Argentina's history. The lessons learned from this well can help Argentinian producers select the best completion method for large-scale development of unconventional resources in the Vaca Muerta Shale.