Fire & Lightning: Mt Etna Erupts In Sicily Ejecting Lava 1Km Into Air

Mt. Etna erupts with a spectacular display of ash and lightning (Credit: Marco Restivo/Demotix/Corbis)

After two years of quiescence, Mount Etna erupted this past Thursday with a spectacular display of lava and volcanic ash. Southern Italy woke up to ashen sky and a red glow above Sicily coming from Mt. Etna on the eastern edge of the island. The active volcano produced one of the most violent eruptions in recent decades and lasted in total less than an hour.

The eruption sent lava up to 1 km (0.6 miles) shooting into the sky and an ash plume 3 km (1.9 miles) into the sky. On top of the spectacular display of molten rock and volcanic ash, volcanic lightning surrounded the ash plume. The volcanic lightning, also called a dirty thunderstorm, is produced as the volcanic ash builds up electric charge by rubbing against other particles. This combination produces a charge imbalance that results in lightning strikes in areas of dense ash.

Scientists have witnessed low-level Strombolian eruptions in the past few weeks that were an indication of increasing activity within the volcano. The Strombolian eruptions led to the major eruption this past Thursday and were the first significant eruption from the Voragine Crater in over two years. Mt. Etna is both the highest and most active volcanoes in Europeand is commonly depicted in historical texts.

Ash cloud from recent Mount Etna eruption (Credit: Marco Restivo/Demotix/Corbis)

Mount Etna’s Geologic Origin

Mount Etna is a stratovolcano sitting on the east coast of Sicily, Italy. The volcano sits on the edge of a convergent plate boundary between the Eurasian Plate and the African Plate. The subduction of the African Plate underneath the Eurasian Plate could be the underlying mechanism that forms the volcano you see today. However, you may notice on plate boundary maps that the Etna volcano sits in front of the subduction zone, rather than directly on it. This has puzzled geologists as to the origin of Mt. Etna and whether a different mechanism is producing the volcano.