Activity of Agung, Anak Krakatau and Rincon de La Vieja

An eruption occurred at Agung on the island of Bali on April 4, 2019 at 01:31 WITA, accompanied by a column of ash observed at ± 2,000 m above the summit (± 5,142 m above sea level). The column of ash was gray, of a thick intensity, bending towards the west. This eruption is recorded on a seismogram of maximum amplitude of 25 mm and a duration of ± 3 minutes 37 seconds. A roaring roar was heard as far as Rendang Station.

VAAC Darwin issued two ash dispersion notices. The first indicated their dispersion towards the west; the second stipulates that the ash cloud is disconnected from the volcano and is supposed to dissipate within 6 to 12 hours. The satellite shows the persistence of a hot spot. The VONA is orange.

Currently, G. Agung is in level III / siaga with recommendations:

(1) to communities around Mount Agung and mountaineers / visitors / tourists not to mount or carry out any activity within the estimated danger zone, ie all areas within 4 km of the crater of the Agung. The estimated risk area is dynamic and continues to be evaluated. It can be modified at any time to follow the latest / most recent observation data from G. Agung.

(2) communities that reside and move around the rivers flowing in Gunung Agung in order to realize the potential secondary threat of lahars that can occur especially during the rainy season.

Source: PVMBG, KESDM

The clear weather on Anak Krakatau has brought good sights to the Sentinel 2 satellite this 3rd of April.

There is an orange color of the sea near the volcano, due to the iron hydroxide produced by submarine volcanic activity.

It can be seen that the vegetation was destroyed on Lang Island, with no recovery at present.

The PVMBG reports for April 3 an eruption earthquake, 3 superficial volcanic earthquakes and 5 low frequency earthquakes; a continuous tremor is always recorded with a dominant amplitude at 1 mm.

The activity level remains at 2 / waspada, with a 2km forbidden zone

Sources: PVMBG and Sentinel 2

In Costa Rica, two phreatic eruptions are noted at Rincon de La Vieja, respectively, these 1st and 3rd of April.

A whitish coloration of the northern flank of the volcano is observed, due to the expulsion of sediments from the crater lake on March 29 at 20:43.

On April 1, a phreatic episode occurred at 8:02, accompanied by a white plume of gas and water vapor.

On April 3, at 2:35 pm, another phreatic episode is responsible for the emission of a slightly larger plume of steam and gas.

It should be noted that Mirova reports three times moderate thermal anomalies on April 3, respective VRP of 16, 18 and 75 MW.

Sources: RSN & Mirova