The first eruption occurred at 12:26 a.m. with an eruption column observed at approximately 700 meters above the summit. This was followed by eruptions at 12:36 a.m., 5:32 a.m., 5:53 a.m., 6:46 a.m., and 9:37 a.m.
"Mount Semeru erupted at 6:46 a.m., with an eruption column observed at approximately 900 meters above the summit," an officer at the Mount Semeru Observation Post, Sigit Rian Alfian, said in a report received on Wednesday.
According to him, the eruption column was observed to be white to gray in color, with a thick intensity moving to the north and northeast.
The eruption was recorded on a seismograph with a maximum amplitude of 16 mm and a duration of 120 seconds.
During the 9:37 a.m. eruption, no visual evidence of the eruption was observed. The eruption was recorded on a seismograph with a maximum amplitude of 22 mm and a duration of 105 seconds.
Mount Semeru is currently at Level III (Alert) status, prompting the Center for Volcanology and Geological Hazard Mitigation (PVMBG) to issue several recommendations.
"The public should not engage in any activity in the southeastern sector along Besuk Kobokan, within 13 km of the summit (the eruption epicenter)," Alfian emphasized.
Beyond that distance, the public is also prohibited from carrying out activities within 500 meters of the riverbank along Besuk Kobokan due to the potential for expansion of pyroclastic flows and lava flows up to 17 km from the summit.
"The public is advised not to carry out activities within a five-kilometer radius of the crater/peak of Mount Semeru due to the risk of ejected (incandescent) rocks," Alfian continued.
Furthermore, residents must be aware of the potential for pyroclastic flows and lava flows along rivers and valleys that originate at the summit of Mount Semeru, especially along Besuk Kobokan, Besuk Bang, Besuk Kembar, and Besuk Sat, as well as the potential for lava flow in small rivers that are tributaries of Besuk Kobokan.
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Translator: Zumrotun Solichah, Resinta Sulistiyandari
Editor: M Razi Rahman
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