Karangetang Erupts, Sending Lava Up to 1 Kilometer
An eruption on Indonesia’s Siau Island sent incandescent material hundreds of meters into the air and lava downhill as authorities warned of hazards near river channels.
SIAU ISLAND, Indonesia — A volcanic eruption on a small Indonesian island sent lava as far as 1 kilometer from Karangetang’s northern crater on Friday, prompting warnings for residents and visitors to keep clear of the volcano and river channels below its slopes.
The eruption occurred at 6:17 p.m. Central Indonesia Time (WITA) on Nov. 13, 2026, on Siau Island in North Sulawesi province. Incandescent material rose about 300 to 400 meters, while no ash column was observed, according to Muhamad Fadlan Rasyidin, an observer at the Karangetang volcano monitoring post.
The small explosive eruption at the northern crater registered a maximum seismic amplitude of 50 millimeters and lasted about 1 minute and 45 seconds, Fadlan said. Incandescent lava fragments fell from near the summit and moved down several sectors of the volcano.
Flows traveled about 700 to 1,000 meters to the west-southwest, with potential routes toward the Hiung, Sumpihi, Kinali, Pangi and Kiawang rivers. Material moved about 500 to 700 meters northwest, potentially toward the Batuare, Batukole and Malrbuhe rivers. Lava also flowed about 500 to 700 meters south.
Residents warned to avoid hazard zones
Karangetang remains at Level II, or Alert, on Indonesia’s four-tier volcanic alert system. Authorities advised residents and tourists not to approach either crater, hike on the volcano or conduct other activities within 1.5 kilometers of the northern and southern craters.
A sector extending south-southwest is also within the forecast hazard zone, out to 2.5 kilometers. The warning covers areas that could be reached by volcanic material, not only hiking routes near the summit.
Volcanic observers said lava avalanches and pyroclastic flows could occur at any time. Lava deposits from earlier activity remain unstable and could collapse, particularly toward the south, southeast, west and southwest.
People living along rivers that rise near Karangetang’s summit were urged to remain alert for rain-triggered lahars and flash floods. Volcanic debris can travel downstream and reach the coast, authorities warned.
