Lava flows as Indonesia's Mount Merapi continues to erupt

Indonesia’s Mount Merapi is continuing to erupt, forcing authorities to halt tourism and mining activities on the slopes of the country’s most active volcano

Indonesia’s Mount Merapi continued to erupt Friday, forcing authorities to halt tourism and mining activities on the slopes of the country’s most active volcano.

The volcano on the densely populated island of Java unleashed clouds of hot ash shortly before midnight Wednesday into early morning Thursday and fast-moving pyroclastic flows — a mixture of rock, lava and gas — traveled up to 5 kilometers down its slopes. It was Mount Merapi’s biggest lava flow since authorities raised its danger level in November 2020, said Hanik Humaida, the head of Yogyakarta’s Volcanology and Geological Hazard Mitigation Center.

Dozens of light eruptions continued during the day Thursday with a river of lava and searing gas clouds flowing 2.5 kilometers down its slopes. No casualties were reported. About 253 people were evacuated to temporary shelters but they returned to the volcano’s fertile slopes after the activity subsided, Ms. Humaida said.

The volcano eruption on Friday spewed a column of hot clouds rising 100 metres (yards) into the air with avalanches of incandescent lava at least 15 times, according to the Geological Disaster Technology Research and Development Center. Using seismic and other data, the agency estimated the lava spread less then 2 kilometers from the crater.

Eko Budi Lelono, who heads Indonesia’s Geology and Volcanology Research Agency, said residents living on Merapi’s slopes were advised to stay 7 kilometers away from the crater’s mouth and should be aware of the danger posed by lava.

He said the lava dome just below Merapi’s southwest rim and the lava dome in the crater both have been active since last year. The volume was estimated at 1.5 million cubic meters in the southwest rim dome and 3.2 million cubic meters in the crater before partially collapsing in the past two days, sending pyroclastic flows traveling fast down the southwest flank.