A remote volcano in southeastern Iran is showing signs of life after roughly 700,000 years of dormancy. According to a new study, the Taftan volcano has risen by about 3.5 inches (9 centimeters) in less than a year, suggesting that pressure is quietly building beneath its summit.
Using satellite radar data, scientists detected the subtle uplift between July 2023 and May 2024. The rise has not subsided, indicating that the pressure remains trapped underground. Researchers led by Pablo J. González from Spain’s National Research Council believe the signal points to movement in Taftan’s hydrothermal system, where hot gases and fluids circulate below the surface.
Taftan is one of Iran’s most isolated volcanoes, with no continuous monitoring equipment like GPS sensors or seismometers. Scientists instead relied on InSAR, a satellite-based radar technique that measures ground motion from space using Sentinel-1 satellites. This approach allows them to watch the volcano from afar, even through clouds and darkness.
The team’s models suggest the pressure source lies only 1,600 to 2,000 feet (roughly 500 to 630 meters) beneath the surface. That shallow depth points to trapped gases rather than magma itself. Taftan’s deeper magma reservoir, sitting more than two miles below, appears quiet for now. Instead, gases rising through fractures seem to be slowly inflating the summit like a balloon.
Taftan stands at 12,927 feet (3,940 meters) and still vents sulfur and steam through summit fumaroles, a clear sign that heat and gas continue to move within the mountain. While there’s no record of a historical eruption, scientists warn that “extinct” can be a misleading label for volcanoes. Dormant systems often stay quiet for millennia before reawakening.
The study ruled out heavy rainfall or nearby earthquakes as triggers, concluding that internal processes are driving the uplift. The most likely explanation is gas buildup in cracks and rock pores, or a small pulse of molten material that released volatile gases upward. As some of that gas escapes, the rate of ground rise has slowed.
This doesn’t mean an eruption is imminent, but it does mean the volcano deserves close attention. The main threat isn’t lava—it’s phreatic explosions, steam-driven bursts that can occur when superheated fluids suddenly turn to vapor. Such blasts can hurl rocks and ash locally, while sulfur gases may affect nearby communities. The city of Khash, only 50 kilometers away, could even catch whiffs of sulfur under the right wind conditions.
“It has to release somehow, either violently or more quietly,” González said. “This study isn’t meant to alarm people, but to urge authorities to begin real monitoring.”
Researchers now hope to install gas sensors and seismometers around Taftan to measure sulfur dioxide, carbon dioxide, and water vapor levels, which can reveal whether pressure is rising or easing. For now, satellites will continue to keep watch from orbit, tracking every subtle shift.
The findings, published in Geophysical Research Letters, serve as a reminder that even volcanoes long thought to be silent can stir again – and that patient, quiet observation is often the first line of defense against surprise eruptions.