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 |
|---|---|---|---|
| 16 February 1986 | 16 June 1986 | 1 | NE flank (ca. 3600 m) · Observations: Reported |
| 22 December 1949 | 16 January 1950 | 1 | SW flank · Observations: Reported |
| 2 July 1878 | — | 1 | SW side · Observations: Reported |
| 1030 ± 40 years | — | ? | Isotopic: 14C (uncalibrated) |
| 70 ± 100 years | — | 4 | San Antonio (upper SW flank) · Isotopic: 14C (calibrated) |
| 1,080 BCE ± 150 years | — | ? | Isotopic: 14C (calibrated) |
| 4,740 BCE ± 200 years | — | ? | Isotopic: 14C (calibrated) |
| 5,720 BCE ± 200 years | — | ? | Isotopic: 14C (calibrated) |
| 5,940 BCE ± 500 years | — | ? | Isotopic: 14C (uncalibrated) |
| 9,450 BCE ± 150 years | — | ? | Isotopic: 14C (calibrated) |
Data: Global Volcanism Program, Smithsonian Institution (#341130)