Mount Lewotolok Activity Declines, Status Remains at Level II

Eruptions were sometimes accompanied by rumbling and booming sounds of weak to moderate intensity. Officers also observed fire glow at the summit and incandescent material ejected into the crater during eruptions.

Kupang (ANTARA) - The Lewotolok Volcano Observation Post reported that volcanic activity at Mount Ile Lewotolok in Lembata Regency, East Nusa Tenggara, showed a decline during the 16–31 July 2026 period, but its status remains at Level II, or Waspada, with a two-kilometre danger radius.

Lewotolok volcano observer Stanislaus Ara Kian from Lembata said on Monday that, based on an evaluation by the Geological Agency through the Centre for Volcanology and Geological Hazard Mitigation (PVMBG), eruption and emission activity at Mount Ili Lewotolok had decreased, with eruption column heights reaching 600 metres above the summit.

“Visual observations during the 16–31 July 2026 period show that eruption and emission activity has declined. The eruption column height reached 600 metres, while the emission smoke column reached 200 metres above the summit,” he said.

Eruptions were sometimes accompanied by rumbling and booming sounds of weak to moderate intensity. Officers also observed fire glow at the summit and incandescent material ejected into the crater during eruptions.

During that period, no lava flow activity was observed.

From seismic observations, 821 eruption earthquakes, four rockfall earthquakes, 1,312 emission earthquakes, 15 harmonic earthquakes, and 17 non-harmonic tremors were recorded.

In addition, two low-frequency earthquakes, four hybrid earthquakes, seven shallow volcanic earthquakes, 27 deep volcanic earthquakes, 10 local tectonic earthquakes, and nine distant tectonic earthquakes were recorded.

PVMBG stated that the number of seismic events during the period generally declined, with emission earthquakes dominating the seismic record.

Shallow and deep volcanic earthquakes were still recorded in relatively stable numbers. The appearance of these earthquakes indicates rock fracturing caused by magma supply from depth towards shallower levels.

“This condition could increase pressure on the body of Mount Ile Lewotolok,” he said.

Meanwhile, deformation observations using the Electronic Distance Measurements (EDM) method showed fluctuations in the slope distance that tended to lengthen.

Deformation observations also indicated deflation, or deflation of the volcano’s body, which is thought to be related to the considerable amount of eruptive material still being released during volcanic activity.

PVMBG recommends that residents and tourists not enter or carry out activities within a two-kilometre radius of the centre of activity at Mount Ili Lewotolok.

Residents are also asked to be aware of the potential for lava avalanches or collapses and pyroclastic flows on the southern and southeastern sectors, the western sector, and the northeastern sector of the volcano.

PVMBG reminded residents not to panic when hearing rumbling or booming sounds from the crater because this phenomenon is part of the activity of a volcano that is undergoing an eruption phase.

To anticipate the impact of volcanic ash, residents are advised to use masks to protect the nose and mouth as well as equipment to protect the eyes and skin.