Why in News?

The Hayli Gubbi volcano in Ethiopia has erupted explosively, sending high-altitude ash plumes thousands of metres into the atmosphere. Parts of this plume have drifted into Indian airspace, prompting India’s aviation authorities to issue advisories to airlines. The volcano is located in the Afar region of northeastern Ethiopia, within the Danakil Depression — one of the hottest and lowest places on Earth.

Geological evidence suggests that this volcano has erupted after nearly 12,000 years, making this event exceptionally significant in the study of African rift-zone volcanism.

Geological Context: The East African Rift System (EARS)

The eruption highlights the active geology of the East African Rift System, one of the world’s most tectonically dynamic regions.

• It is here that the Arabian, Nubian, and Somali plates are diverging.
• Continental rifting, volcanic fissures, and frequent earthquakes are common.
• The region is dominated by basaltic lava and fissure-type eruptions.

The Danakil Depression itself is a classic example of an area where the continental crust is thinning and pulling apart, allowing magma to rise easily to the surface.

What Happened During the Eruption?

The Hayli Gubbi eruption, reported on Sunday, was characterised by an explosive release of ash, gases, and fine volcanic particles.
Key observations include:

• No significant lava or magma flow on the ground.
• The volcanic plume likely contained fine rock fragments, volcanic glass, and gases such as SO₂ and CO₂.
• Hot air around the vent rose rapidly due to intense heating, carrying fine particles 15–40 km up into the atmosphere.
• Strong upper-level winds transported the plume across regions, including towards Indian airspace.

This behaviour is typical of explosive eruptions where pressure build-up inside the volcano forces material upward with great force.

Shield Volcanoes: Key Facts

The Hayli Gubbi volcano belongs to the category of shield volcanoes.
Important characteristics:

• They are the largest volcanoes on Earth by volume.
• Formed by repeated eruptions over long geological timescales.
• Composed mainly of basaltic lava, which is fluid and spreads over wide distances.
• Have broad, gently sloping profiles rather than steep, conical shapes.

Understanding Volcanic Eruptions

A volcanic eruption refers to the expulsion of gases, molten rock (magma/lava), and solid fragments from beneath the Earth’s surface through vents or fissures.

How Eruptions Occur

• Earth’s mantle contains a weaker zone called the asthenosphere, where magma forms.
• Dissolved gases in the magma expand rapidly as pressure reduces near the surface.
• This increase in pressure forces magma through cracks, producing an eruption.

Eruption Materials

• Lava (once magma reaches the surface)
• Pyroclastic debris
• Volcanic ash and dust
• Volcanic bombs
• Gases such as sulphur dioxide, nitrogen compounds, and carbon dioxide

Recent Volcanic Incidents Worldwide

• Sabancaya (Peru, 2025)
• Ruang (Indonesia, 2025)
• Etna (Italy, 2025)
• Kilauea (USA, 2024)

These eruptions highlight increasing global volcanic activity monitoring and the importance of early warnings for aviation.

Consequences of Volcanic Eruptions

Positive Impacts

• Provide scientific information about Earth’s interior
• Source of geothermal energy
• Temporary global cooling due to aerosol emissions

Negative Impacts

• Air pollution and acid rain
• Aviation hazards due to ash clouds
• Seismic disturbances leading to earthquakes
• Destruction of property and risk to human life

Conclusion

The rare eruption of the Hayli Gubbi volcano after nearly 12,000 years is a major geological event with international implications. It highlights the volatility of the East African Rift System and the interconnected nature of Earth’s atmospheric circulation, where an eruption in Ethiopia can have direct consequences for aviation safety in India. Continuous monitoring of volcanic activity, especially in tectonically dynamic regions like Afar, remains crucial for global disaster preparedness and scientific understanding.