The Tumalo volcano spread ignimbrites and plinian deposits in ground eruptions across the area , similar to the eruption of Vesuvius that destroyed Pompeii . These deposits spread from Tumalo to the town of Bend . Basaltic lava flows from North Sister overlay the youngest Tumalo pyroclastic deposits , indicating that North Sister was active more recently than 260,000 years ago
eruption of Vesuvius that destroyed Pompeii
Eruption of Mount Vesuvius in 79
Three Sisters (Oregon)