KVERT reported that an explosive eruption at Zhupanovsky continued during 19-26 September. Ground-based observers noted ash plumes drifting SW to Avachinsky Bay during 23-24 September. Satellite images detected a thermal anomaly during 18 and 23-24 September, as well as ash plumes that rose to altitudes of 3.5-4 km (11,500-13,000 ft) a.s.l. and drifted 80 km SW and NE during 23-24 September. The Aviation Color Code remained at Orange.

Geological Summary. The Zhupanovsky volcanic massif consists of four overlapping stratovolcanoes along a WNW-trending ridge. The elongated complex was constructed within a Pliocene-early Pleistocene caldera whose rim is exposed only on the eastern side. Three of the stratovolcanoes were built during the Pleistocene. An early Holocene stage of frequent moderate and weak eruptions from 7,000 to 5,000 years before present (BP) was followed by a period of infrequent larger eruptions that produced pyroclastic flows. The last major eruption took place about 800-900 BP. Recorded eruptions have consisted of relatively minor explosions from Priemysh, the third cone from the E about 2.5 km from the summit peak.

Source: Kamchatkan Volcanic Eruption Response Team (KVERT)