Ten Fun and Possibly Explosive Facts about Volcanoes

HUMBOLDT AND BONPLAND with CHIMBORAZO in the background| WIKIMEDIA, PUBLIC DOMAIN

Andrea Wulf starts her book The Invention of Nature with Humboldt’s ascent in 1802 of Chimborazo, a dormant volcano which at the time was thought to be the tallest peak in the world. He made it as high as 19,200 feet before retreating due to altitude sickness.

Chimborazo is believed to have last erupted in 550 AD, though South America is still home to active volcanoes and earthquakes. Wulf describes how earlier in the same journey Humboldt had experienced his first earthquake in 1799 in Cumaná (in what is now Venezuela). He was shaken, literally and figuratively – describing his reaction thus – ‘we mistrust for the first time a soil, on which we had so long placed our feet with confidence.’

Humboldt was convinced that earthquakes and volcanoes sprang from the same subterranean cause – well ahead of his time on this topic as he was on so many. Both have long been subjects of study and a source of fascination for their powers of quick and unexpected destructive capability. So here, 218 years after Humboldt’s ascent of Chimborazo, are my Ten Fun and Possibly Explosive Facts about Volcanoes:

1. Chimborazo, once thought to be the tallest – In the 17th and 18th centuries, Chimborazo, an inactive volcano, was thought to be the world’s highest peak, leading to many attempts to summit it, including Humboldt’s. It wasn’t until 1880 that the English climber Edward Whymper, along with two Italian guides made it to the top. Though Chimborazo is no longer considered the highest peak by elevation above sea level, it is still acknowledged as the farthest peak from the earth’s core, benefiting from its location on the “equatorial bulge” of the globe. While currently inactive, recent study shows it could erupt again. The average time between eruptions of Chimborazo is 1,000 years, and it’s now more than 1,400 years since the last known eruption.

2. Mount Tambora, largest eruption – In April 1815 Mount Tambora on the island of Sumbawa in Indonesia erupted. Up to 100,000 people are estimated to have been killed, directly or indirectly, in what is commonly thought to be the largest volcanic eruption ever observed. More than 12 cubic miles of gas, dust and rock exploded into the air and onto the island. A third of the mountain was displaced, shrinking the peak elevation from 14,100 feet to 9,354 feet. Eruptions began on April 5th, and climaxed on April 10th, but continued for another six months. Volcanic ash in the atmosphere was dispersed around the world, lowering global temperatures. The following year, 1816 became known as the year without a summer.

3. Indonesia and USA – #1 Volcano Countries – The United States is home to the largest number of volcanoes at 173. Russia is second with 166. Indonesia comes in third overall with 139 volcanoes, though is credited with having the largest number of active volcanoes at 76.

4. One Ring to Rule Them All – The Pacific Ocean is circled by the active earthquake and volcano zone known as the “Ring of Fire”, circling the Americas, Asia, Japan and Australasia. The Ring of Fire has 452 of the more than 1500 volcanoes the Global Volcanism Program says have erupted at some point in the Holocene period (the last ~11,500 years).

5. Plate Tectonics – The notion of tectonic plates is relatively recent. The idea that plates – large surfaces of the Earth – “float” on the hot core of the Earth and push and pull against one another, was developed early in the 20th century. The movement of these plates cause the continents to “drift”, and at their edges where plates butt against each other are areas of increased volcanism, earthquakes and geysers. Seven (or eight depending on the classification) major plates have been identified, along with dozens of smaller plates.

6. Yellowstone Supervolcano – Not all volcanoes can be conclusively tied to plate tectonics. The Yellowstone “supervalcano” has produced three large eruptions in and around today’s Yellowstone National Park. The last of the three eruptions was over 600,000 years ago. This volcanic activity, along with the geothermal activity leading to Yellowstone’s famous geysers are thought to be caused by a bulge or “hotspot” of molten magma rising from the earth’s mantle below the Park. One theory suggests this hotspot is an isolated geographic weakness in the Earth’s crust, while another theory suggests that the hotspot results from subduction of an ancient plate completely below the current North American plate, weakening the current plate at Yellowstone.

7. Mauna Loa – According to the US Geological Survey, Mauna Loa on the island of Hawaii (i.e. the “Big Island”) is the largest active volcano in the world. Mauna Loa rises 13,000 feet above sea level. It’s flanks descend 3 miles to the sea floor, and it’s great weight actually depresses the sea floor another 5 miles, making it’s peak 10 and 1/2 miles above its base. Since 1843 Mauna Loa has erupted 33 times, most recently in 1984.

8. Pompeii – Pompeii and Herculaneum are two ancient Roman cities preserved by the blast of Mount Vesuvius in 79 AD. Pictures of a well preserved street vendor’s stand in Pompeii were recently in the news. The stand was fronted with well preserved frescoes depicting chickens and mallards – fare that may have been served there. In Herculaneum the ash that covered that city carbonized and preserved wood in roofs, doors and beds, as well as food and papyrus documents. Both ancient cities have been designated World Heritage Sites, and are located in the Vesuvius National Park, founded in 1995.

9. Volcano as the Oldest Story on Earth – Among the Gunditjmara people of the current state of Victoria in Australia, a story has been passed down for countless generations. The story relates how the creator transformed into a fiery volcano known as Budj Bim. Recent mineral dating measurements by Australian scientists suggest that this story may be an actual account of volcanic eruptions that took place 37,000 years ago. If this is correct, that would mean that the Gunditjmara people’s story is the oldest known story still being told. A stone axe buried beneath lava from those eruptions provides independent evidence that people were in the area at the time the volcano erupted.

10. Most Active Volcano – Kilauea volcano is considered the most active volcano in the world. Mt Etna is Europe’s most active volcano. It also has the longest recorded history of eruptions, dating back to 1500 BC.

So there are my 10 fun facts. Do you have a volcano fact or story to share? Leave a comment below.