This Volcano Collapsed 69 Years Ago—and Has Almost Fully Rebuilt Itself

Russia’s Bezymianny volcano is in the middle of a comeback that would make most geological timelines feel lazy. Sixty-nine years after blowing off its summit in a massive eruption, the mountain has nearly rebuilt itself, and its late-November ash plume pushed that process even further.

Bezymianny sits on the Kamchatka Peninsula in the Russian Far East, a stretch of Earth where volcanoes act with unnerving regularity. In November, it sent an ash cloud about 32,800 feet into the sky, according to the Institute of Volcanology and Seismology. The event marked another chapter in a regrowth story scientists have been documenting for decades.

Before the 1956 collapse, Bezymianny rose at least 10,213 feet above sea level. That eruption blew out the slope, destroyed the summit, and left a horseshoe-shaped crater. A lava dome formed almost immediately inside that open cavity and kept growing, eruption after eruption, until the volcano began regaining its classic cone shape.

A 2020 study that analyzed flight photographs from 1949 to 2017 showed that Bezymianny added an average of 26,400 cubic meters of rock per day over that period. Researchers estimated the mountain could reach its pre-collapse height sometime between 2030 and 2035. Co-authors Alexander Belousov and Marina Belousova told Live Science that “the most surprising thing was the fast growth of the new volcanic edifice.”

The scientists also noted that volcanoes with this horseshoe-style crater history can collapse again, which can set off another major explosive eruption. The rebuilding process is impressive, but it comes with a sort of geological warning label that keeps volcanologists from getting too comfortable.

Bezymianny’s recovery hasn’t come only from headline-grabbing ash blasts. Flyover images and fieldwork show decades of effusive lava flow, beginning in 1977. As its lava became less silica-rich and less viscous, it spread more easily and stacked into new layers, gradually restoring the volcano’s height and symmetry.

Monitoring continues through satellites, ground stations, webcams, and repeated survey flights. Belousov and Belousova said this long record of collapse and regrowth helps scientists forecast long-term behavior at other volcanoes with similar histories, including Mount St. Helens.

Researchers expect more growth, more lava, and more reshaping ahead. Bezymianny’s long rebuild continues to play out in real time.