Part 5/10:
The most familiar of these is the asteroidal impact that struck 66 million years ago, leading to the extinction of the dinosaurs. But geological evidence suggests that volcanic super-eruptions played a substantial role in other mass extinctions.
The Toba Supereruption: A Near-Extinction Event
One of the most significant volcanic events was the eruption of the Toba supervolcano approximately 74,000 to 75,000 years ago. With a Volcanic Explosivity Index (VEI) of 8—the highest level on the scale—Toba was an eruption of unprecedented magnitude. To put this into perspective, Mount St. Helens had a VEI of 5, and its eruption was devastating but far less catastrophic on a global scale.