KVERT reported that a thermal anomaly over Alaid was identified in satellite images on 17 and 22 December; weather clouds obscured observations on the other days during 16-21 December. The Aviation Color Code remained at Orange (the second highest level on a four-color scale). Dates are based on UTC times; specific events are in local time where noted.

Geological Summary. The highest and northernmost volcano of the Kuril Islands, Alaid is a symmetrical stratovolcano when viewed from the north, but has a 1.5-km-wide summit crater that is breached open to the south. This basaltic to basaltic-andesite volcano is the northernmost of a chain constructed west of the main Kuril archipelago. Numerous pyroclastic cones are present the lower flanks, particularly on the NW and SE sides, including an offshore cone formed during the 1933-34 eruption. Strong explosive eruptions have occurred from the summit crater beginning in the 18th century. Reports of eruptions in 1770, 1789, 1821, 1829, 1843, 1848, and 1858 were considered incorrect by Gorshkov (1970). Explosive eruptions in 1790 and 1981 were among the largest reported in the Kuril Islands.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)