An eruption of Mount Sinabung, north Sumatra on May 7, 2021 at 9:08 a.m. WIB, with an ash plume observed ± 2800 m above the summit (± 5260 m above sea level). - photo Magma Indonesia
This May 7, 2021, Magma Indonesia reports 2 eruptions in Sinabung between 00 and 12 h.
Seismicity is characterized by:
- 2 eruption earthquakes, with an amplitude of 55 and 120 mm, lasting 210 and 356 sec.
- 116 collapse / avalanche earthquakes,
- 4 emission earthquakes and
- a low frequency earthquake.
The level of activity remains unchanged, at 3 / siaga, with the usual no-go zones.
Source: Magma Indonesia
At Pacaya, the activity remains mainly effusive.
Insivumeh observes a white and bluish fumarole at Mackenney crater, moving south.
The effusion continues on the new crack of the NE flank; the lava flow descends towards the SW and reaches 2,300 m. long. One of the flows does not move, and another moves slowly.
Heavy rains hit Guatemala causing floods, landslides and lahars; A moderate lahar is reported in the Rio Nima and its tributary the Rio Samala, drainages of the Santiaguito.
The eruption that began at Piton de La Fournaise on 04/09/2021 at 7 p.m. (appearance of the tremor) continues. The amplitude of the volcanic tremor (indicator of a surface lava emission), after stagnating from April 29 to May 1, resumed its tendency to slowly decrease since May 2. Its amplitude remains significant, however, still reaching 50% of the maximum amplitude observed during this eruption on April 13.
The two cones are still active, with degassing which is always more marked at the level of the most downstream cone; the flow of the lava at the exit of the eruptive mouths, is done mainly in tunnels and this almost to the upper limit of the large slopes, where resurgences of lava are visible on the surface, and the flow front continues its slow progression at the top of the Grandes Pentes.
Over the past 24 hours, 7 superficial volcano-tectonic earthquakes (between sea level and the surface) have been recorded, all located directly above the summit craters.
Soil CO2 fluxes are still increasing in the far field (Plains region) suggesting that deep recharge is continuing.
The slight inflation (swelling) of the summit zone continues, which testifies to a pressurization of the surface reservoir in accordance with its recharge by deeper magma. This confirms the interpretation derived from observations of CO2 fluxes in the soil.
Seismic activity at La Soufrière in St. Vincent has remained low since the earthquake associated with the April 22 explosion and ash dump.
In the past 24 hours, only a few long-period hybrid and volcano-tectonic earthquakes have been recorded and there have been no other earthquakes.
The volcano continues to be in a state of turmoil.
The government of Saint Vincent and the Grenadines has lowered the volcanic alert level at La Soufrière to ORANGE based on a recommendation from the University of the West Indies Seismic Research Center (UWI-SRC).
At the ORANGE alert level, the volcano can resume explosions with less than twenty-four hours notice. Lahars (mudslides) remain a dangerous secondary hazard and pose a dangerous threat to the river valleys surrounding the volcano, including Wallibou and Rabacca. The mudslides observed over the past few days were composed of rocks up to 5 m. of diameter. Scientists have also observed vapor flows, which are likely due to contact and incorporation of hot volcanic deposits. Lahars can cause property damage and serious injury to people in their path.
As a result, the government of Saint Vincent and the Grenadines has also decided that residents of Orange Zone communities from Petit Bordel to Gordon Yard on the leeward side of the island and up to Mt. Young people near the RUBIS gas station, on the windward side of the island, can go home and perform normal activities.
The communities of Chateaubelair, Fitz-Hughes and all the communities in the danger zone of the red volcano remain restricted.
Sources: UWI-SRC, NEMO, SVG