October 06 , 2017. EN. Nevados de Chillan , Popocatepetl , Shinmoedake , Ambae .
October 06 , 2017.
Nevados de Chillan, Chile :
During the period, 1825 seismic events, of which 88 (88) were classified as volcano-tectonic (VT) events, related to fracturing processes of rigid materials with maximum local magnitudes (ML) of 1.8. The most powerful earthquake was located 1.5 km east-southeast (ESE) of the active crater at a depth of 3.0 km.
Similarly, there were recorded 1737 earthquakes associated with fluid dynamics within the volcanic edifice, 1507 of which were cataloged as long-period (LP) events with reduced maximum displacement values (DRc) of 271.6 cm2, a value considered to be strong. In addition, 225 tremor-type (TR) earthquakes were recorded with maximum displacement values of 65.3 cm2, a value also considered to be high.
Finally, there were recorded 5 long-term events, termed « Tornillos » type, in connection with the transit of magmatic and / or hydrothermal fluids inside volcanic conduits, with high impedance contrast characteristics, and reduced displacement values of less than 1.5 cm2.
Between 15 and 30 September, a total of one hundred and seventeen explosions associated with ash emissions and / or recording of acoustic signals collected by microphones installed on the slopes of the volcano were presented, continuing with the explosive phase that this volcano has shown since the beginning of 2016. The explosion that released the highest seismic energy was recorded on 19 September at 07:18 local time and was associated with an earthquake that had a displacement reduced by 174 cm2.
The images obtained through the cameras installed near the volcanic complex showed mainly fumaroles associated with the emission of water vapor and ash from the currently active craters with column heights less than 1800 m above the crater.
According to the data provided by the GNSS stations, no deformation is observed due to changes in the morphology of the volcano. The data provided by the inclinometer stations display stable positions over time.
No emissions of sulfur dioxide (SO2) into the atmosphere have been reported in the area near the volcanic complex, according to data published by the Ozone Monitoring Instrument (OMI) Sulfur Dioxide Group (http: // so2.gsfc.nasa.gov/) and the National Environmental Satellite Information and Data Service (NESDIS) (http://satepsanoine.nesdis.noaa.gov).
No thermal alert was reported in the area associated with the volcanic complex according to the data processed by the IR (MIROVA) (http://www.mirovaweb.it/) and the thermal time monitoring the Global Hot-Spots (MODVOLC) (http://modis.higp.hawaii.edu/).
During the second half of September, an explosive activity of pulsating nature was recorded, emitting gases and particles at maximum heights of nearly 1,800 m above the crater level, with vulcanian features apparently associated with l the interaction of a small volume of magma which reacts with the surface hydrothermal system, destabilizing it and causing minor explosions with the subsequent emission of materials in a pulsed manner. This explosive phase has seen more explosive events than previous phases, in decline in numbers and energy in recent days. Therefore, in the current scenario, it is possible to continue this process with the generation of explosions of similar size or even larger than those recorded.
The Volcanic Technical Alert is maintained at:
YELLOW LEVEL: Changes in the behavior of volcanic activity – Probable time for eruption: WEEKS / MONTHS.
Remarks: Preventive restrictions are recommended to access an area of 3 km radius around the crater.
Source : Sernageomin
Popocatepetl , Mexico :
Early on Thursday, 5 October 2017, the Popocatépetl volcano recorded an explosion accompanied by an emission of incandescent fragments at a distance of 600 meters from the crater.
The civil defense of the state of Puebla reports that the explosion occurred at 2:25, and added that the column of smoke reached a height of 2 kilometers in a western direction.
The volcanic cone was covered with incandescent materials. A moderate ash fall was reported in the municipalities of Totolapan and Ocuituco in Morelos.
The National Center for Disaster Reduction (Cenapred) stated that this activity is being considered in the alert scenarios, so that the level of volcanic activity continues at Amarillo Phase 2.
Although the volcano is currently calm, Cenapred has asked the population to be attentive to the official information broadcast. Monitoring is maintained 24 hours a day.
Over the past 24 hours, 11 low-intensity exhalations and three explosions were recorded today at 02:26, 03:26 and 03:27, according to the seismic monitoring systems of the Popocatépetl volcano. As a result of these events, there was a report of slight ash falls in the cities of Totolapan, Tlalnepantla and Cuernavaca in Morelos State and in Ecatzingo, Atlautla and Tepetlixpa of the State of Mexico.
Two volcanotectonic earthquakes were also recorded yesterday at 5:14 p.m. and 5:15 p.m. with a magnitude of M2,2 and M2,0, respectively. Moreover, in the afternoon, due to heavy rains, reports of lahares were received, occurring in some of the ravines on the western side of the volcano, without causing any damage. It should be mentioned that the above is envisaged in the scenarios already predicted for the yellow phase 2 activity level of the volcanic alert semaphore fire.
In addition to the above, a harmonic tremor segment was recorded, which started today at 08:55 h and ended at about 09:24 h accumulating a total duration of 30 minutes.
Source : El popular , Cenapred .
Photo : Webcamdemexico
Shinmoedake , Japan :
Shinmoedake volcano eruption warning raised to Level 2 as tremors increase
Kyodo Oct 6, 2017
The Meteorological Agency has raised warning levels against volcanic eruptions by one notch for Shinmoedake peak in the Kirishima mountain range on the border between Kagoshima and Miyazaki prefectures.
The agency took the step late Thursday night, saying it issued a Level 2 warning for Shinmoedake in light of a recent series of small volcanic tremors observed in the area.
A Level 2 warning restricts entry to areas near the mouth, while a Level 1 warning only tells the public the existence of a volcano. Level 5, the highest alert, urges people to evacuate.
According to the agency, 12 tremors were observed on Shinmoedake on Sept. 23, and 39 on Oct. 4. The number continues to rise.
Given the developments, small-scale eruptions could occur soon, and rocks could be spewed within a 1-km radius from the mouth, the agency said.
The agency lowered its warning level from 2 to 1 on May 26 after signs that volcanic activity had subsided.
Source : Japantimes
Ambae , Vanuatu :
AMBAE VOLCANO ALERT BULLETIN No13 issued by the Vanuatu Meteorology and Geohazards Department (VMGD) on 6th October 2017 at 15:11PM :
Eruptive activity remains stable at Ambae. The Alert Level for Ambae volcano is lowered to Level 3 from Level 4.
The volcanic eruption at Ambae is continuing but remains stable and confined to Lake Voui. Further scientific analyses confirm that there is currently no evidence of escalation of the activity. As a consequence, the Volcanic Alert Level is lowered to Level 3 from Level 4. The volcanic eruption is likely to continue in a steady state. Danger is restricted to the danger zone that extends 3 km from the active vent in Lake Voui.
Observation flights on 30th of September, 1st, 3rd and 5th October 2017 confirm the activity at the volcano is only occurring in one of the summit crater lakes (Lake Voui) and is not changing. Photographs and thermal infrared images taken during observation flights show the activity consists of small explosions and ejection of hot rocks from vents on the new small island in the lake. There is also a small lava flow from the island into the lake. A small-scale eruption continues in Lake Voui at Ambae volcano.
These observations and the analysis of seismic, gas and deformation data by scientists from the Geohazards Division of the Vanuatu Meteorology and Geohazard Department (VMGD) and international scientists confirms that the volcano has settled in a more stable state of activity. The activity at Ambae is like what is seen and experienced at Yasur on Tanna Island. The local population can hear some of the explosions and see glow over the mountain at night.
The eruption at Ambae started in September, when the Volcanic Alert Level was raised to Level 3. The volcanic activity has built a volcanic cone (island) in Lake Voui. The cone building phase produced the largest explosions and ashfalls. Some parts of the island experienced ashfalls from this phase of the eruption. The eruptions in mid-September 2017 are similar to those in 2005.
The style of the eruption changed around 22 September when Geohazards staff observed lava (molten rock) at the surface for the first time. This was a significant change and raised the level of uncertainty about the development of the eruption. The volcanic Alert Level was also raised at that time to Level 4.
Ambae volcano is a very large volcano and is frequently active. In the recorded history, there have been many eruptions, every 10-50 years over the past 150 years. All have been from the summit craters, except one recorded in 1670’s when a lava flow occurred in the Ndui Ndui area. The current eruption is focused in the summit crater and there are no indications of activity elsewhere on Ambae Island.
The danger zone is now within 3 km from the vent in Lake Voui. In this area flying rock and volcanic gases may be present (See map below). Villages located further away may experience volcanic hazards from gas plumes, especially villages exposed to prevailing trade winds direction.
The Vanuatu Meteorology and Geohazards Department will continue to closely monitor this volcano activity. More information will be provided as available.
Source : VGO