There have been some big eruptions in recent history, like Mount Pinatubo, Mount St. Helens, and even Krakatoa. But those were tiny compared to some of the largest eruptions that have ever happened in the Earth’s history. So what was the largest eruption ever?
First, let’s get a sense of scale. When Krakatoa exploded in 1883, it released more than 21 cubic kilometers of rock, ash and pumice measuring 6 on the Volcanic Explosivity Index. At least 36,000 people died in the eruption and the tsunamis that followed.
Well, that was nothing.
Lake Toba in Indonesia measures 100 km long and 30 km wide and goes down to a depth of 505 meters. But it’s actually the collapsed caldera of a supernova that detonated about 74,000 years ago. Geologists believe that it erupted with an intensity of 8 on the Volcanic Explosivity Index, releasing 2,800 cubic kilometers of ash, rock and pumice. It deposited a layer of ash 15 centimeters thick over the entire Indian subcontinent.
Want bigger? No problem. The La Garita Caldera eruption in Colorado erupted about 28 million years ago, blasting out 5,000 cubic kilometers of ash.
We have written many articles about volcanoes for Universe Today. Here’s an article about supervolcanoes, and here’s an article about the Krakatoa eruption.
We have also recorded an episode of Astronomy Cast about Earth, as part of our tour through the Solar System – Episode 51: Earth.