KVERT reported that, according to observers in Severo-Kurilsk (Paramushir Island) about 7 km E, a gas-and-steam plume continuing ash rose from Ebeko to an altitude of 1.5 km (4,900 ft) a.s.l. and drifted 15 km ENE on 20 October. The Aviation Color Code was raised to Yellow (the second lowest on a four-color scale). Later that day observers noted gas, steam, and ash plumes rising 1.3-1.4 km (4,300-4,600 ft) a.s.l. and drifting 10 km NE. Ground-based and satellite observations during 21-23 October indicated quiet conditions; the Aviation Color Code was lowered to Green on 24 October.

Geological Summary. The flat-topped summit of the central cone of Ebeko volcano, one of the most active in the Kuril Islands, occupies the northern end of Paramushir Island. Three summit craters located along a SSW-NNE line form Ebeko volcano proper, at the northern end of a complex of five volcanic cones. Blocky lava flows extend west from Ebeko and SE from the neighboring Nezametnyi cone. The eastern part of the southern crater contains strong solfataras and a large boiling spring. The central crater is filled by a lake about 20 m deep whose shores are lined with steaming solfataras; the northern crater lies across a narrow, low barrier from the central crater and contains a small, cold crescentic lake. Historical activity, recorded since the late-18th century, has been restricted to small-to-moderate explosive eruptions from the summit craters. Intense fumarolic activity occurs in the summit craters, on the outer flanks of the cone, and in lateral explosion craters.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)