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 |
|---|---|---|---|
| 320 BCE ± 16 years | — | 5 | Ninahuilca Chico II dome · Isotopic: 14C (uncalibrated) |
| 2,490 BCE ± 40 years | — | 5 | Ninahuilca Chico I dome · Isotopic: 14C (uncalibrated) |
| 3,490 BCE ± 100 years | — | 4 | Arenal II dome · Isotopic: 14C (uncalibrated) |
| c. 6,910 BCE | — | 4 | La Cocha II dome · Isotopic: 14C (uncalibrated) |
Data: Global Volcanism Program, Smithsonian Institution (#352021)