Why Perfectly-Shaped Volcanoes are Deadly

Fagjun | Published 2018-01-26 20:16

Mayon volcano, one of the most active volcanoes in the Philippines, is known for its perfectly conical shape. While this shape makes the volcano beautiful to look at, it’s also evidence of how dangerous Mayon is.


Mount Mayon in its calmer days [Photo by Tomas Tam]

Mount Mayon in its calmer days [Photo by Tomas Tam]

 

When Mayon is asleep, it’s a harmless tourist attraction. People flock to Albay province in the Philippine island of Luzon to trek up the volcano’s symmetrical slopes, and even attempt to reach the rim at the summit. The volcano is undeniably beautiful, but its beauty is far from harmless or the result of a random geological process. The symmetry in the volcano’s shape is actually indicative of how frequently it erupts.

 

Mayon began spewing smoke, ash, mud, and rocks on January 13, and has launched a few lava fountains from its crater in what could be a preparation for a big eruption. The last big Mayon explosion occurred in 2001, with smaller eruptions happening in 2006 and 2009.



Beautiful but Dangerous


Mayon volcano spraying lava in a recent volcanic eruption. [Photo by EPA]

Mayon volcano spraying lava in a recent volcanic eruption. [Photo by EPA]

 

The volcano’s first recorded eruption was in 1616, and there have been about 58 known volcanic events since then. In fact, there were four in just the past decade. In 1814, Mayon experienced its most explosive eruption, sending columns of ash miles into the sky and killing 1200 people in surrounding towns. Mount Vesuvius, the volcano that famously preserved the town of Pompeii in ash and preserved everyone and everything in it, has erupted over 50 times in comparison. It killed about 2,000 people in Pompeii.

 

A nighttime eruption [Photo by Reuters]

A nighttime eruption [Photo by Reuters]

 

Mayon’s eruptions are typically what scientists call “strombolian”. This means that the volcano sprays out molten rock, which then collects around the rim of the crater. Each strombolian eruption emits more of the same, and the volcanic rocks eventually stack up and form the steep slopes that Mayon is known for.

 

Though many of Mayon’s eruptions are strombolian in nature, the volcano is still capable of explosive eruptions. Just in 2001, Mayon’s eruption came with a roar reminiscent of that of a jet plane. Clouds of ash and molten rock shot over six miles into the sky. Another concern over Mayon’s possible explosion is lahar, or the flow of pyroclastic debris that can worsen with heavy rains—which the Philippines gets a lot of.



Imminent Explosion


Mayon emits a pillar of smoke and ash in the background as people try to go about their business as usual. [Photo by EPA]

Mayon emits a pillar of smoke and ash in the background as people try to go about their business as usual. [Photo by EPA]

 

The biggest question is still if and when Mayon will have a dangerous, explosive eruption. While it’s possible that an explosion is imminent, it’s also still possible that volcanic activity will subside. Volcanic eruptions are notoriously difficult to predict, because the magma underneath the Earth’s crust is constantly flowing.

 

However, it’s better to be safe than sorry, and this is especially true when there’s an active volcano involved. A level 4 alert, just a notch under the highest alert level, is still in place in Albay province, where Mayon is located. Tens of thousands of people have also been relocated from their homes near the volcano, and authorities say that areas near Mayon may be under a three-month-long emergency status. Unfortunately, residents may need to stay away from their homes for that long. Still, these measures are necessary to ensure that though Mayon volcano is dangerous, it no longer needs to be deadly.

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