Based on visual observations during clear weather, CVGHM reported that on 25, 26, 30 and 31 October, white and gray plumes from Soputan rose to altitudes of 1.8-3.3 km (5,900-10,800 ft) a.s.l. and drifted W. A lava flow traveled between 500-600 m down the W flank on 25 October and was again spotted on 30 October. The Alert Level remained at 3 (on a scale of 1-4) and villagers and tourists were advised not go within a 6 km radius of the summit.

Based on visual observations during clear weather, CVGHM reported that on 25, 26, 30 and 31 October, white and gray plumes from Soputan rose to altitudes of 1.8-3.3 km (5,900-10,800 ft) a.s.l. and drifted W. A lava flow traveled between 500-600 m down the W flank on 25 October and was again spotted on 30 October. The Alert Level remained at 3 (on a scale of 1-4) and villagers and tourists were advised not go within a 6 km radius of the summit.

Geological Summary. The Soputan stratovolcano on the southern rim of the Quaternary Tondano caldera on the northern arm of Sulawesi Island is one of Sulawesi's most active volcanoes. The youthful, largely unvegetated volcano is the only active cone in the Sempu-Soputan volcanic complex, which includes the Soputan caldera, Rindengan, and Manimporok (3.5 km ESE). Kawah Masem maar was formed in the W part of the caldera and contains a crater lake; sulfur has been extracted from fumarolic areas in the maar since 1938. Recent eruptions have originated at both the summit crater and Aeseput, a prominent NE-flank vent that formed in 1906 and was the source of intermittent major lava flows until 1924.

Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM), Darwin Volcanic Ash Advisory Centre (VAAC)