[BUENOS AIRES, SciDev.Net] The extraction of gas and oil by fracking—large-scale fracturing of underground rocks by injecting water, sand and additives—is generating growing concern in Argentine Patagonia.

Neuquén province—home to the country’s largest hydrocarbon reserves—has experienced an increase in earthquakes since fracking operations began there in 2015.

In January, a report by the independent consulting firm NCS Multistage revealed that 2026 began with an exceptionally high number of fracturing operations in the area. Continuing at the same rate, this year is expected to set a record for the activity.

Luciano Fucello, author of the report and professor of petroleum engineering at the Buenos Aires Institute of Technology, told SciDev.Net that there was a correlation between hydrocarbon production and the tremors reported by residents of Sauzal Bonito and Añelo, in Neuquén province.

“During the [COVID-19] pandemic, when activity stopped, the earthquakes stopped. And when it resumed, they returned,” he said.

Together with Plaza Huincul and Cutral Co, these towns form an oil producing region that, at the end of 2025, generated more than 570,000 barrels of shale oil and 64 million cubic metres of shale gas a day.

Both are unconventional hydrocarbons, meaning they require large-scale hydraulic fracturing to produce because they are attached to a source rock.

In 2013, a legislative reform enabled fracking in Vaca Muerta, a 30,000 square kilometre formation that today represents—along with grains and oils— the country’s main source of foreign currency.

Following the subsequent expansion of fracking, the number of earthquakes recorded in territories near the operations has increased—in places where they were not usually felt before. The tremors were strong enough to cause cracks in buildings, leaving many homes uninhabitable.

The Induced Seismicity Observatory, created by local experts, has recorded 442 tremors on its website since the end of 2018, when seismic activity intensified.

Javier Grosso, a geographer and one of the observatory’s founders, told SciDev.Net that the updated figure exceeded 600.

In 2025 alone, the observatory recorded 102 tremors in Añelo, near Sauzal Bonito and Rincón de los Sauces, where seismic activity is expanding. This is a record number, which Grosso attributes to the increase in fracking operations.

“The entire subsoil is being investigated, and it is beginning to show a sensitivity it did not have before,” he said.

In an analysis published in the journal Nature, Grosso and colleagues observed “vertical displacements” since 2017, following periods of intense industrial activity. This included a 4.9 magnitude earthquake in March 2019.

The fracturing of rocks “produces a seismic wave that travels through the subsoil,” Grosso explained. “The tremor is the response to the injection and extraction of fluid, the readjustment of tectonic plates that respond to these enormous pressures.”

When the wave reaches populated areas, residents feel noises and tremors, sometimes strong enough to knock over furniture and appliances and even cause structural damage.

The Argentine Institute of Petroleum and Gas, which brings together public and private corporations in the sector, did not respond to SciDev.Net ‘s requests for information for this article.

In statements to BBC News in January, it maintained that the only way to determine the origin of the tremors was to establish a “baseline” that identifies the mobility of the entire basin—something it said was still pending due to infrastructure issues.

There are concerns about the oil industry’s water usage. A shale well needs up to 60,000 cubic metres. Image Credit: jwigley/Pixabay

But according to Grosso, “Vaca Muerta has the most seismic monitoring equipment in all of Latin America. The National Institute for Seismic Prevention has nine seismographs and private companies have between 21 and 25.”

“For us, the word of the inhabitants is just as valuable as instrumental records,” he added.

“We have residents who have been in the area for 60 years and they tell us this never happened before.”

Fucello acknowledges the high productivity of fracking, with the wells producing up to three times as much as conventional ones. But he warns that the activity requires constant reinvestment.

Environmentalists also raise concerns about the industry’s water usage. While a conventional well may require 6,500 cubic metres of water, a shale well needs up to 60,000 cubic metres.

Much of that volume is unrecoverable, and what is returned is usually reinjected into abandoned wells.

Sand consumption is also high. “Last year, five million tonnes were used for fracking in Vaca Muerta,” said Fucello. “This year it will be six million,” he predicted.

“Conventional deposits [extracted using traditional methods] consume 100 times less,” he added.

Fracking also generates large quantities of contaminated solid waste, warns Santiago Cané, a lawyer specialising in the impacts of this industry at the Inter-American Association for Environmental Defense.

In 2024, a geospatial analysis by the National Geographic Institute of Argentina warned about the “potential for critical contamination” in the Negro River basin, due to the high density of wells, many located near bodies of water, agricultural and urban areas.

Although no country in Latin America has banned fracking, the Brazilian states of Paraná and Santa Catarina do not allow it, while in Colombia six bills to eliminate it were rejected by Congress. In Mexico, president Claudia Sheinbaum appears willing to promote it to reduce dependence on natural gas from the United States, a stance that has revived the debate about fracking in the region.

This article was produced by SciDev.Net’s Latin America and Caribbean desk.