Old Wells, New Tricks: Gas Boost for Vaca Muerta

A new study suggests that “huff-n-puff” gas injection could revive aging shale wells and cut costs in Argentina’s Vaca Muerta.

31 Jul 2025

Argentina's shale producers might have found a way to squeeze more oil from the Vaca Muerta without drilling a single new well.

A new study presented at the 2025 Unconventional Resources Technology Conference suggests that recycled gas reinjection, known in the industry as "huff-n-puff," could significantly improve recovery rates from tight rock. The key: precise control over injection timing and pressure cycles.

Earlier attempts at this method produced mixed results. But this time, researchers combined high-resolution reservoir models with real-time production data. The new simulations track how gas moves through Vaca Muerta's maze of fractures and tight layers. Their conclusion? When done right, gas reinjection can breathe new life into aging wells at a fraction of the cost of drilling new ones.

State-backed YPF has taken notice. With inflation pushing up development costs, the company is evaluating pilot projects that reuse gas already produced from its wells. The move could reduce flaring and cut down on trucking, two big operational headaches.

"This could be a smart lever for us," said an engineer involved in the planning. "If the pilots work, we can extend well life without major surface disruption or big new investments."

Still, success depends on knowing exactly what's happening underground. Each well's geology is unique, so engineers will need real-time data from fiber optics or downhole sensors to fine-tune the reinjection process.

If the pilots go well, huff-n-puff could become a go-to strategy. It offers a middle ground: more oil, less carbon, and no need to rush into expensive new drilling. In a tight budget environment, that combination is hard to ignore.

For Argentina, the stakes are high. Vaca Muerta is the country's most important energy asset. If this technique works, it could become a model not just for YPF but for shale producers across Latin America.