Holiday Ayo - A volcano in Iran that has been dormant for approximately 700,000 years is suddenly showing signs of an impending eruption.

New research published October 7 in the journal Geophysical Research Letters found that the ground near the summit of Mount Taftan in Iran rose 3.5 inches over a 10-month period from July 2023 to May 2024.

This indicates increased gas pressure beneath the volcano's surface.

Volcanoes are considered extinct if they have not erupted during the Holocene, which began 11,700 years ago.

Given Mount Taftan's recent increase in activity, experts believe it may be more accurately described as dormant.

"It will erupt somehow in the future, either violently or more slowly," study senior author Pablo González, a volcanologist at the Institute of Natural Products and Agrobiology, a research center of the Spanish National Research Council (IPNA-CSIC), told Live Science.

He said there is no reason to worry about an imminent eruption, but the volcano needs to be monitored closely.

Taftan Volcano is a 12,927-foot (3,940-meter) stratovolcano in southeastern Iran, located among mountains and volcanoes formed by the subduction of Arabian oceanic crust beneath the Eurasian continent.

The volcano currently has an active hydrothermal system and smelly sulfur-producing vents called fumaroles, but its eruptions are unknown in human history.

When Mohammadhossein Mohammadnia, a doctoral student working under González's guidance at IPNA-CSIC, first examined satellite imagery of the volcano in 2020, he saw no evidence of volcanic activity.

However, in 2023, residents began reporting gas emissions from the volcano on social media. The emissions could be smelled from the town of Khash, about 31 miles (50 kilometers) away.

Mohammadnia again examined satellite imagery from the European Space Agency's Sentinel-1 mission.

Taftan is remote and lacks the GPS monitoring systems found on volcanoes like Mount St. Helens.

The region is also dangerous due to insurgent activity and the border conflict between Iran and Pakistan.

The satellite imagery showed a slight uplift near the summit, indicating increased pressure below.

Mohammadnia calculated that the driver of this uplift lies 1,608 to 2,067 feet (490 to 630 m) below the surface.

It's impossible to know for certain what's happening, but researchers have ruled out external factors like earthquakes or nearby rainfall.

The volcano's magma reservoir is more than 2 miles below the surface, much deeper than any factor that could have driven the uplift.

Instead, the uplift is caused by changes in the hydrothermal vents beneath the volcano that are causing a buildup of gas, or a small amount of magma may have shifted beneath the volcano, allowing gas to bubble into the overlying rocks, increasing pressure in the pores and fractures of the rock, and causing the ground to slightly lift.

The next step in the research, according to González, is to collaborate with scientists who monitor gases at the volcano.

"This study is not intended to cause panic among the public. It's a call to authorities in the Iranian region to allocate resources to review this," González explained.