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A magnitude 5.4 earthquake that struck the South Korean city of Pohang in November 2017 was likely triggered by an experimental geothermal plant, two new studies say.

The studies published this week in the journal Science provide concurrent evidence that injections of water several miles underground by a $38-million pilot geothermal plant "almost certainly induced" South Korea's second-strongest quake since records began in 1978 and the most destructive quake in the country's history.

The quake injured 82 people and damaged more than 200 homes in the city located about 170 miles southwest of Seoul. It is a densely populated metropolis and home to more than half a million residents.

"The Pohang earthquake was larger than any predicted by existing theories,” said Kwanghee Kim, a seismologist at Pusan National University in Busan, South Korea, and lead author of one study.

(MORE: Oklahoma's Earthquake Threat Now Equals That of California's, USGS Says)

Kim and his colleagues determined that the quake originated just below the well used to inject wastewater into the Earth's surface. They believe injections were introduced in or near active seismic fault lines, according to the journal Nature.

The findings could prove a "game-changer" in the hydro-geothermal power plant industry, says Jin-Han Ree, a structural geologist at Korea University in Seoul, and a lead author on one of the studies.

Numerous Oklahoma quakes have been blamed on "fracking." Hydraulic fracturing, as fracking is known by its more technical term, has also been blamed for quakes in the United States and other countries. The temblor in South Korea, however, is much larger than the largest known geothermal-linked quake recorded in Basel, Switzerland, in 2006. That quake registered magnitude 3.4.

Kim said the evidence should be a "wake-up call" that companies' use of hydraulic fracturing needs to change.

The evidence comes as a blow to South Korea and other countries that are relying on geothermal technologies to provide carbon-free energy sources.