Lajas Formation - Cupen Mahuida: The Most Important Tight-Sand Gas Development in South America

摘要

Cupen Mahuida field is located some 70km west northwest of the city of Neuquen, in the Neuquen's Basin. The Lajas Formation dates from the Mid-Jurassic age. Its thickness reaches up to 1000m of sediment that includes reservoirs of fine to coarse sandstones and conglomerates. Tight features include: Low permeability (0.001 to 0.03 mD) multilayer nature, proximity to its source rock and significant net pay (Net to Gross: 40-50%). Some other characteristics that put it away from other more orthodox definitions include: lack of over-pressure (200-300kg/cm~3), water production and a proved structural influence in productivity. The first massive fractures for Lajas Fm. took place in 2005, since then, more than 170 wells were drilled including infill and horizontal wells. Today, this project accounts for 25% of YPF Gas Production in this basin (including Vaca Muerta Shale Gas), and the last five years it has added between 30% and 60% of total YPF Reserves for the Neuquen province.