On Kadovar, Papua New Guinea, the eruption continues, with thick vapor emissions to the main crater, rising to a hundred meters above the summit, and a continuous steam plume at the coastal lava dome , rising a hundred meters above the island, dissipated to the southeast.
The lava flow continues to grow; a distinct lobe has traveled 20-30 m. from the nose of the flow towards the open sea, seeming channeled between "levées" developed on its sides.
At 18:30 LT, on February 1, a collapse of the side of the flow, facing the island of Blup Blup, generated a plume of gray ash; the vigorous degassing then continued, shining brightly enough during the night.
The main body of the flow swelled upwards, with a distinct valley now visible between the bulge and the flank of the island.
The lava dome continues to grow on the southeast coast
At the seismicity level, high frequency episodes are recorded, mixed with the signals of strong winds and waves.
A detailed map of the new topography would be welcome.
Source: Rabaul volcano Observatory - report 18 / 02,02,2018
Topographic evolution of the Kadovar island-volcano between 2.09.2017 and 24.01.2018 - satellite images ALOs-2 and Terra SAR-X - AIT Geology Document Center - Sentinel ASIA - Sources: Esri, HERE, DeLorme, Intermap, Increment Corp, GEBCO, USGS, FAO
After the change of type of activity, which became vulcanienne yesterday January 1, the first major eruptive episode of 2018 Fuego ended after about twenty hours.
During this paroxysm, four lava flows were emitted, as well as a series of pyroclastic flows in the Seca, Trinidad, Las Lajas and Honda barrancas.
Fuego had not experienced such intense activity since 1974.
Fuego - summit incandescence and deposits of pyroclastic flows in different drainages 01.02.2018 - Landsat image 8 SWIR bands 7-6-2- Nasa via Rüdiger Escobar Wolf
Fuego - ash plume extension on 01.02.2018 - - Landsat image 8 SWIR bands 7-6-2- Nasa - via Rüdiger Escobar Wolf
Only a few benign explosions persist, accompanied by ash plumes at 4,700 m.asl., moving for 15 km. The lava fountains are no longer observed.
The liberated energy graph RSAM has returned to normal.
The Conred reports that the departments of Chimaltenango, Escuinta, Suchitepéquez and Sacatepéquaz, about 48,000 people, have been affected; 19 incidents are reported, as well as the evacuation of 2880 people.
Sources: Insivumeh special volcanolgic bulletins # 10 & # 11 & CONRED
At Mayon, a quiet effusion of lava and degassing are observed at the summit crater; lava feeds the flows in the Miisi and Bonga-Buyuan drainages, which advanced respectively 3.2 and 4 km. from the top.
The observatory reports that the land covered by the flows will not be usable for a long time, because the lava is solodified into a hard rock ... the cone of the Mayon could become an uninhabitable area.
Mayon - 01.02.2018 / 22h30 loc. - lava flows in the Miisi and Bonga drainages - Arnolf Lorcha's Photo
The monthly OVPF bulletin concerning Piton de La Fournaise has just been published:
The volcano-tectonic activity under the Piton de la Fournaise massif thus remained weak in January 2018.
Throughout the month of January 2018, far-field GPS stations (at the base of the terminal cone and out of the Enclosure) continued to record a slow, continuous inflation, witnessing the pressurization of a deep source.
The main change comes from the stations around the summit craters which recorded during the first 18 days of January a high inflation (up to 1.2 cm of elongation of the summit zone in 2.5 weeks). This effect was also felt on the stations at the base of the terminal cone (up to 1.5 cm elongation) and in the far field (excluding Enclosure) but to a lesser extent (<0.5 cm elongation).
This high inflation observed at the level of the Piton de la Fournaise summit zone could be linked to a strong hydrothermal activity following the heavy rains of January (~ 1st fortnight of the month). The large influx of water into the superficial hydrothermal system and the rise in heat associated with a deep recharge (below sea level) have led to a thermal expansion of these hydrothermal fluids, at the origin of the inflation observed during the month (~ first half of the month).
Piton de La Fournaise - Illustration of the summit deformation over 2 months. Here is shown a baseline (variation of distance between two GPS receivers) crossing the crater Dolomieu. A rise is synonymous with elongation and therefore swelling of the volcano; conversely, a decrease is synonymous with contraction and therefore deflation of the volcano. Any periods colored in light pink correspond to eruptions.
At the level of the gases:
- Top emissions from the Piton de la Fournaise: persistence of low concentrations of H2S and sometimes SO2 in the air at the top of the volcano.
- CO2 concentrations in the soil at the level of the volcano deposit: intermediate concentrations. As with the deformations, the CO2 measurements were affected by the poor weather conditions of the first half of the month. The next steps will therefore be to follow.
All these observations show for the month of January :
- a deep re-feeding in magma (below sea level) which is maintained;
- a pressurization of the superficial magmatic reservoir which remains weak;
- a significant hydrothermal activity in the first half of the month in connection with heavy rainfall.