About the volcano
The eruption of Novarupta on the Alaska Peninsula lasted about 60 hours in June 1912 and reached VEI 6 – by volume of magma it was the largest of the 20th century. The magma drained from beneath neighbouring Mount Katmai, whose summit collapsed to form a caldera. The valley below was filled with pyroclastic-flow deposits tens of metres thick, from which thousands of fumaroles steamed for years; explorer Robert Griggs named it the Valley of Ten Thousand Smokes. The area was almost uninhabited, so the eruption claimed no lives. Today it is part of Katmai National Park.
Eruption history
VEI – Volcanic Explosivity Index: 0 = lava outpouring, 4 = like Eyjafjallajökull 2010, 6 = like Pinatubo 1991, 7 = like Tambora 1815. The scale is logarithmic – each step is about 10 times more material.
| Start | End | VEI | Vent and dating |
|---|---|---|---|
| 6 June 1912 | 16 October 1912 | 6 | Observations: Reported |
Data: Global Volcanism Program, Smithsonian Institution (#312180) · Wikipedia (pl) · Wikipedia (en)