Topic: Earth Science

A huge body of magma rose from deep underground and stopped just beneath an island in Portugal's Azores archipelago. This caused thousands of earthquakes, but the magma never erupted.

Magma is molten rock that flows beneath our feet. In March 2022, a massive surge of magma moved upward from over 20 kilometers below the surface to just 1.6 kilometers beneath São Jorge Island in Portugal's Azores archipelago. This rapid movement happened quietly, with little seismic activity during its ascent. The enormous intrusion unfolded within just a few days and involved enough magma to fill roughly 32,000 Olympic-sized swimming pools.

Scientists used seismometers on land and at sea to pinpoint earthquake activity. They also analyzed satellite and GPS measurements to monitor how the island's surface shifted during the event. Satellite data revealed that the ground above the volcano rose by about 6 centimeters, confirming that magma had entered the shallow crust beneath the island.

The magma traveled upward through one of São Jorge Island's major fault systems known as the Pico do Carvão Fault Zone. This fault zone likely acted as a pathway that guided the magma upward and allowed gases and fluids to escape sideways, reducing pressure within the magma and preventing it from erupting.

Why It Matters

This study helps us understand how volcanic islands are built and reshaped over time. It also provides new insights into how scientists can forecast volcanic hazards and improve their warnings.

Key Facts

• A massive surge of magma rose from deep underground to just beneath São Jorge Island in Portugal's Azores archipelago.
• The magma traveled upward through one of the island's major fault systems, known as the Pico do Carvão Fault Zone.
• The rapid movement happened quietly, with little seismic activity during its ascent.
• The enormous intrusion unfolded within just a few days and involved enough magma to fill roughly 32,000 Olympic-sized swimming pools.
• The magma never erupted, but triggered thousands of earthquakes instead.

Key Terms

Magma

Molten rock that flows beneath our feet

Implications

This study helps us understand how volcanic islands are built and reshaped over time. It also provides new insights into how scientists can forecast volcanic hazards and improve their warnings.