The long-dormant Hayli Gubbi volcano in northeastern Ethiopia erupted on Sunday, sending ash nine miles into the sky, its first known major eruption in over 12,000 years.

Axar.az, citing Scientific American, reports that scientists say the volcano is poorly studied, and satellite data suggest it may have had smaller, unnoticed eruptions in the past.

The event is unusual because Hayli Gubbi is a shield volcano, which typically produces slow lava flows rather than massive ash columns.

The volcano lies within the East African Rift Zone, where tectonic plates are slowly pulling apart, creating ideal conditions for magma formation.

Recent activity at the nearby Erta Ale volcano, along with ground deformation and steam emissions, indicated that an eruption was possible. The blast poses little risk to people due to its remote location but has triggered a rapid scientific investigation to analyze ash samples and better understand the region’s volcanic history.